WO2011070397A1 - Hybrid vanadium catalysts and use thereof in selective cycloalkane oxidation processes - Google Patents

Hybrid vanadium catalysts and use thereof in selective cycloalkane oxidation processes Download PDF

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WO2011070397A1
WO2011070397A1 PCT/IB2009/055665 IB2009055665W WO2011070397A1 WO 2011070397 A1 WO2011070397 A1 WO 2011070397A1 IB 2009055665 W IB2009055665 W IB 2009055665W WO 2011070397 A1 WO2011070397 A1 WO 2011070397A1
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oxidation
hybrid
catalyst
cycloalkanes
acid
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PCT/IB2009/055665
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Portuguese (pt)
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Gopal S. Mishra
Pedro Melo Bandeira Tavares
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Universidade De Trás-Os-Montes E Alto Douro
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    • B—PERFORMING OPERATIONS; TRANSPORTING
    • B01—PHYSICAL OR CHEMICAL PROCESSES OR APPARATUS IN GENERAL
    • B01J—CHEMICAL OR PHYSICAL PROCESSES, e.g. CATALYSIS OR COLLOID CHEMISTRY; THEIR RELEVANT APPARATUS
    • B01J31/00—Catalysts comprising hydrides, coordination complexes or organic compounds
    • B01J31/16—Catalysts comprising hydrides, coordination complexes or organic compounds containing coordination complexes
    • B01J31/22—Organic complexes
    • B01J31/2204—Organic complexes the ligands containing oxygen or sulfur as complexing atoms
    • B01J31/2208—Oxygen, e.g. acetylacetonates
    • B01J31/2226—Anionic ligands, i.e. the overall ligand carries at least one formal negative charge
    • B01J31/2243—At least one oxygen and one nitrogen atom present as complexing atoms in an at least bidentate or bridging ligand
    • B—PERFORMING OPERATIONS; TRANSPORTING
    • B01—PHYSICAL OR CHEMICAL PROCESSES OR APPARATUS IN GENERAL
    • B01J—CHEMICAL OR PHYSICAL PROCESSES, e.g. CATALYSIS OR COLLOID CHEMISTRY; THEIR RELEVANT APPARATUS
    • B01J31/00—Catalysts comprising hydrides, coordination complexes or organic compounds
    • B01J31/16—Catalysts comprising hydrides, coordination complexes or organic compounds containing coordination complexes
    • B01J31/1616—Coordination complexes, e.g. organometallic complexes, immobilised on an inorganic support, e.g. ship-in-a-bottle type catalysts
    • B01J31/1625—Coordination complexes, e.g. organometallic complexes, immobilised on an inorganic support, e.g. ship-in-a-bottle type catalysts immobilised by covalent linkages, i.e. pendant complexes with optional linking groups
    • B01J31/1633—Coordination complexes, e.g. organometallic complexes, immobilised on an inorganic support, e.g. ship-in-a-bottle type catalysts immobilised by covalent linkages, i.e. pendant complexes with optional linking groups covalent linkages via silicon containing groups
    • B—PERFORMING OPERATIONS; TRANSPORTING
    • B01—PHYSICAL OR CHEMICAL PROCESSES OR APPARATUS IN GENERAL
    • B01J—CHEMICAL OR PHYSICAL PROCESSES, e.g. CATALYSIS OR COLLOID CHEMISTRY; THEIR RELEVANT APPARATUS
    • B01J2231/00—Catalytic reactions performed with catalysts classified in B01J31/00
    • B01J2231/70—Oxidation reactions, e.g. epoxidation, (di)hydroxylation, dehydrogenation and analogues
    • B—PERFORMING OPERATIONS; TRANSPORTING
    • B01—PHYSICAL OR CHEMICAL PROCESSES OR APPARATUS IN GENERAL
    • B01J—CHEMICAL OR PHYSICAL PROCESSES, e.g. CATALYSIS OR COLLOID CHEMISTRY; THEIR RELEVANT APPARATUS
    • B01J2531/00—Additional information regarding catalytic systems classified in B01J31/00
    • B01J2531/02—Compositional aspects of complexes used, e.g. polynuclearity
    • B01J2531/0238—Complexes comprising multidentate ligands, i.e. more than 2 ionic or coordinative bonds from the central metal to the ligand, the latter having at least two donor atoms, e.g. N, O, S, P
    • B01J2531/0241—Rigid ligands, e.g. extended sp2-carbon frameworks or geminal di- or trisubstitution
    • B01J2531/0252—Salen ligands or analogues, e.g. derived from ethylenediamine and salicylaldehyde
    • B—PERFORMING OPERATIONS; TRANSPORTING
    • B01—PHYSICAL OR CHEMICAL PROCESSES OR APPARATUS IN GENERAL
    • B01J—CHEMICAL OR PHYSICAL PROCESSES, e.g. CATALYSIS OR COLLOID CHEMISTRY; THEIR RELEVANT APPARATUS
    • B01J2531/00—Additional information regarding catalytic systems classified in B01J31/00
    • B01J2531/50—Complexes comprising metals of Group V (VA or VB) as the central metal
    • B01J2531/56—Vanadium
    • B—PERFORMING OPERATIONS; TRANSPORTING
    • B01—PHYSICAL OR CHEMICAL PROCESSES OR APPARATUS IN GENERAL
    • B01J—CHEMICAL OR PHYSICAL PROCESSES, e.g. CATALYSIS OR COLLOID CHEMISTRY; THEIR RELEVANT APPARATUS
    • B01J31/00—Catalysts comprising hydrides, coordination complexes or organic compounds
    • B01J31/02—Catalysts comprising hydrides, coordination complexes or organic compounds containing organic compounds or metal hydrides
    • B01J31/06—Catalysts comprising hydrides, coordination complexes or organic compounds containing organic compounds or metal hydrides containing polymers
    • B01J31/069—Hybrid organic-inorganic polymers, e.g. silica derivatized with organic groups

Definitions

  • the present invention is in the technical domain of the oxidation reactions
  • Functionalization of saturated hydrocarbons in particular the selective oxidation at low temperatures of cycloalkanes to cycloalkanols and cycloalkanones (processes also referred to as K: A oil), are important reactions in the production of nylon-6,6 ', adipic acid, urethane foams, polyamides-6 and lubricating additives [GB 777087, US 3,530,185].
  • the main products that form during the oxidation are alcohols and ketones [US 7,081,552, US 5,767,320] and adipic acid [US2004 / 0092767 A1].
  • the activity of the catalyst systems is very dependent on the correct choice of solvent, which determines the polarity of the medium and the size of the substrate that needs to be adsorbed on the catalytic surface [Appl. Catch. A: Gen., 2000, 203, 231].
  • the possibility of solvent-free reactions is an advantage in terms of process costs and the efficiency of separation / purification of the reaction products.
  • the object of the present invention is the selection of a hybrid catalyst and the establishment of an economically environmentally favorable process for the oxidation of cyclohexane either in the presence or absence of heterocyclic acids.
  • the actual processes are mainly dependent on the correct choice of reaction conditions and the metal species anchored on the catalytic surface.
  • Commercially cobalt salts are used to achieve this conversion under homogeneous conditions (ie DuPont process for the oxidation of cyclohexane, cobalt (III) salt catalyst with only about -4% conversion and 85% selectivity at 423 K).
  • vanadium catalysts the best published results under dioxygen reaction conditions indicate a maximum conversion of 12% with silica supported vanadium maltolate complexes [J. Mol. Cat. A: Chem. 2005, 239, 96], 13% with silica supported vanadium (II) complexes [Cat. Lett. 2002, 81, 113] and 13% with vanadium scorpionate complexes [PT 104447].
  • vanadium hybrid catalysts immobilized on a carrier containing -OH groups on their surface for the covalent anchoring of the vanadium complex.
  • R 1 and R 2 are independently may be different or equal and may be -H, -X
  • A is a carrier material containing -OH groups on its surface, for example silica, functionalized silica, alumina, functionalized alumina, mesoporous materials among others.
  • Another aspect of the present invention is the application of these vanadium complexes as catalysts in the oxidation reaction of cycloalkanes using dioxygen or air as oxidizing agent.
  • heterocyclic compounds having a conversion of from 30 to 35, and having a high overall selectivity (cyclic alcohols + cyclic ketones) which may reach 97%.
  • FIG. 2 General formula of the oxidation reaction of cycloalkanes to cyclic alcohols and ketones.
  • Hybrid Catalyst - II Hybrid Catalyst - III
  • the reactions were carried out in a high pressure discontinuous micro reactor with 40 cm 3 capacity, temperatures between 100 and 200 ⁇ C, pressures between 5 and 25 bar and reaction times between 180 and 1440 minutes.
  • This reactor had a gas inlet and a pressure gauge.
  • the measurement of the internal temperature and its control was obtained by a thermocouple and an on / off controller.
  • the oxygenation reactions were carried out in this reactor by adding the supported vanadium catalyst to the cycloalkane, (for example cyclohexane).
  • the reactor was then closed, the air removed under vacuum and the 0 2 introduced until the desired pressure.
  • the usual gas used was oxygen, however, air, air enriched with pure oxygen and oxygen diluted with inert gas such as Ar, N 2 or He can be used.
  • the catalysts After the oxidation reactions the catalysts have a light brown color. At the end of the reactions the catalyst was separated from the solution and washed several times with acetone. The catalysts may be regenerated for later use, by heating at 60 ⁇ C, in a static air atmosphere, in a furnace. A catalyst used for 1440 minutes of reaction and regenerated thereafter was found to have substantially the same catalytic power, with no loss of vanadium occurring, although its color changed from green to brown.
  • the selective oxidation process of cycloalkanes with the hybrid vanadium catalysts can further be complemented by the use of heterocyclic acid type cocatalysts such as picolinic acid, 2,6-pyrazinedicarboxylic acid, 5-hydroxy- 2-pyrazinecarboxylic acid, 5-methyl-2-pyrazinecarboxylic acid, 3-aminopyrazine-2-carboxylic acid and 2-pyrazinecarboxylic acid.
  • heterocyclic acid type cocatalysts such as picolinic acid, 2,6-pyrazinedicarboxylic acid, 5-hydroxy- 2-pyrazinecarboxylic acid, 5-methyl-2-pyrazinecarboxylic acid, 3-aminopyrazine-2-carboxylic acid and 2-pyrazinecarboxylic acid.
  • oxygen is a reagent
  • the solid hybrid catalyst can be used for further oxidation reactions simply by adding more 0 2 , even without isolating and reactivating it. This result indicates that the use of a continuous reactor increases the overall yield.
  • the catalyst after use, can be reactivated and recycled under the action of heat.
  • tests were performed under the same reaction conditions as above. The presence of vanadium on the supported catalyst was tested by ICP (inductive couple plasma analyzes) showing that only a small loss of vanadium occurred. Before the first use 0.22% of vanadium (by mass) was determined, which decreased to 0.19% after use (720 minutes) and its regeneration. In subsequent regenerations no decrease in the amount of vanadium was detected. Tests have shown that the regenerated hybrid catalyst has an unchanged catalytic capacity, with an overall conversion yield of 21% (under the same conditions for 720 minutes).
  • a vanadium salt solution (VO (C 5 H 7 0 2) 2, 2xl0 3 mol - 4xl0 3 mol) in THF (5-50 mL) was added under constant agitation to an equimolar amount of bis (salicylidene amino -3-propyl) amine with 3-iodopropyl trialkoxysilane ligand (2x10 3 mol - 4x10 3 mol) in THF (10-55 mL). The mixture was heated under reflux. The final solution formed was concentrated and after addition of an alkane precipitated a green solid. This solid was separated by filtration, washed with the alkane and dried under vacuum to obtain the vanadium complex II (87% yield). This complex is soluble in most polar organic solvents.
  • a vanadium salt solution (VO (C 5 H 7 0 2) 2, 0,5xl0 3 mol - 3xl0 3 mol) in THF (5-50 mL) was added under constant agitation to an equimolar amount of bis ( chloro-salicylidene amino-3-propyl) amine with 3-iodopropyl trialkoxysilane ligand (0.5x10 3 mol - 3x10 3 mol) in THF (10-55 mL). The mixture was heated under reflux. The final solution formed was concentrated and after addition of an alkane precipitated a green solid. This solid was separated by filtration, washed with the alkane and dried under vacuum to obtain vanadium complex III (86% yield). This complex is soluble in most polar organic solvents.
  • the oxidation process was performed in the same manner as in Example 3 except for the use of air instead of oxygen. Analysis of the reaction mixture indicated an overall cyclohexane conversion of 4.5% with a selectivity of 67.2% and 19.3% in cyclohexanol and cyclohexanone, respectively.

Abstract

The present invention relates to new hybrid vanadium catalysts of general formula I wherein: n = 1 to 4; R1 and R2 can be different or the same and independently represent -H, -X (halogen), straight or branched C1 to C4 alkyl, -NO2, -OH, -OMe, -OEt; and A is a support material with -OH functional groups on the surface thereof. The present invention also incorporates the use of these complexes to selective cycloalkane oxidation processes for producing cyclic alcohols and ketones. When used in the oxidation process, the new vanadium catalysts allow high conversion and selectivity with regard to the corresponding reaction products, making use of dioxygen (O2), a cheap oxidant available in the air, under moderate reaction conditions, in the presence or absence of heterocyclic acids.

Description

Description  Description
Title of Invention: CATALISADORES HÍBRIDOS DE VANÁDIO E SUA UTILIZAÇÃO EM PROCESSOS DE OXIDAÇÃO Title of Invention: VANADIUM HYBRID CATALYSTS AND THEIR USE IN OXIDATION PROCESSES
SELECTIVA DE CICLO ALCANOS ALCAN CYCLE SELECTIVE
Domínio Técnico da Invenção  Technical Domain of the Invention
[1] A presente invenção insere-se no domínio técnico das reacções de oxidação  [1] The present invention is in the technical domain of the oxidation reactions
catalisadas por complexos de vanádio.  catalyzed by vanadium complexes.
Antecedentes da Invenção  Background of the Invention
[2] A funcionalização de hidrocarbonetos saturados, em particular a oxidação selectiva a baixas temperaturas de cicloalcanos a cicloalcanóis e cicloalcanonas (processos também designados por K:A oil), são reacções importantes na produção do nylon-6,6', ácido adípico, espumas de uretano, poliamidas-6 e aditivos de lubrificação [GB 777087, US 3,530,185]. Os principais produtos que se formam durante a oxidação são álcoois e cetonas [US 7,081,552, US 5,767,320 ] e ácido adípico [US2004/0092767 Al]. Foram feitos vários esforços para desenvolver novos catalisadores para a oxidação do ciclohexano em condições suaves, com selectividade para os produtos alvo, usando o 02 como oxidante [US 7,166,751 B2], no entanto os sistemas desenvolvidos normalmente não conjugam elevadas conversões com boa selectividade para os produtos desejados . Functionalization of saturated hydrocarbons, in particular the selective oxidation at low temperatures of cycloalkanes to cycloalkanols and cycloalkanones (processes also referred to as K: A oil), are important reactions in the production of nylon-6,6 ', adipic acid, urethane foams, polyamides-6 and lubricating additives [GB 777087, US 3,530,185]. The main products that form during the oxidation are alcohols and ketones [US 7,081,552, US 5,767,320] and adipic acid [US2004 / 0092767 A1]. A number of efforts have been made to develop novel catalysts for the oxidation of cyclohexane under mild conditions with selectivity to target products using the O 2 as oxidant [US 7,166,751 B2], however the systems developed do not normally conjugate high conversions with good selectivity to the desired products.
[3] Para a oxidação em fase homogénea do ciclohexano têm sido propostos vários catalisadores metálicos, tais como crómio, ferro, manganês ou platina, com diversos resultados em termos de conversão do ciclohexano e selectividade em ciclohexanona e ciclohexanol. [ Appl. Catai. A: Gen ., 1996, 135, L7-L11]. Contudo, a aplicação destes catalisadores homogéneos é geralmente condicionada pelo seu curto tempo de vida [WO 00/53550].  [3] For the homogeneous phase oxidation of cyclohexane several metal catalysts have been proposed, such as chromium, iron, manganese or platinum, with various results in terms of cyclohexane conversion and selectivity in cyclohexanone and cyclohexanol. [Appl. Catch. A: Gen., 1996, 135, L7-L11]. However, the application of these homogeneous catalysts is generally conditioned by their short lifetime [WO 00/53550].
[4] A actividade dos sistemas catalíticos é muito dependente da escolha correcta do solvente, o que determina a polaridade do meio e o tamanho do substrato que precisa de ser adsorvido na superfície catalítica [ Appl. Catai. A: Gen ., 2000, 203, 231]. A possibilidade de efectuar reacções sem solventes é uma vantagem em termos de custos processuais e ao nível do rendimento da separação/purificação dos produtos de reacção.  [4] The activity of the catalyst systems is very dependent on the correct choice of solvent, which determines the polarity of the medium and the size of the substrate that needs to be adsorbed on the catalytic surface [Appl. Catch. A: Gen., 2000, 203, 231]. The possibility of solvent-free reactions is an advantage in terms of process costs and the efficiency of separation / purification of the reaction products.
[5] A invenção sob consideração tem por objectivos a selecção de um catalisador híbrido e o estabelecimento de um processo económico, ambientalmente favorável, para a oxidação do ciclohexano, quer na presença, quer na ausência de ácidos heterocíclicos. Os processos actuais são sobretudo dependentes da escolha correcta das condições de reacção e das espécies metálicas ancoradas na superfície catalítica. Comercialmente são utilizados sais de cobalto para obter esta conversão sob condições homogéneas (i.e. processo DuPont para a oxidação do ciclohexano, catalisador de sal de cobalto(III) com apenas cerca de -4% de conversão e 85% de selectividade a 423 K). No caso dos catalisadores de vanádio os melhores resultados publicados em condições de reacção com dioxigénio, indicam uma conversão máxima de 12%, com complexos de maltolato de vanádio suportado em sílica [J. Mol. Cat. A: Chem. 2005, 239, 96], 13% com complexos de vanádio(II) suportados em sílica [Cat. Lett. 2002, 81, 113] e de 13% com complexos de escorpionato de vanádio [PT 104447 ]. The object of the present invention is the selection of a hybrid catalyst and the establishment of an economically environmentally favorable process for the oxidation of cyclohexane either in the presence or absence of heterocyclic acids. The actual processes are mainly dependent on the correct choice of reaction conditions and the metal species anchored on the catalytic surface. Commercially cobalt salts are used to achieve this conversion under homogeneous conditions (ie DuPont process for the oxidation of cyclohexane, cobalt (III) salt catalyst with only about -4% conversion and 85% selectivity at 423 K). In the case of vanadium catalysts the best published results under dioxygen reaction conditions indicate a maximum conversion of 12% with silica supported vanadium maltolate complexes [J. Mol. Cat. A: Chem. 2005, 239, 96], 13% with silica supported vanadium (II) complexes [Cat. Lett. 2002, 81, 113] and 13% with vanadium scorpionate complexes [PT 104447].
[6] Existe por isso a necessidade de encontrar novos catalisadores que permitam, em condições suaves, promover a oxidação de cicloalcanos conjugando boas conversões e selectividade, que permitam que o processo de oxidação se desenvolva na ausência de solvente. There is therefore a need to find new catalysts that allow, under mild conditions, to promote the oxidation of cycloalkanes by conjugating good conversions and selectivity, which allow the oxidation process to develop in the absence of solvent.
Descrição Geral da Invenção  General Description of the Invention
[7] No âmbito da presente invenção encontram-se catalisadores híbridos de vanádio, imobilizados num suporte que contem grupos -OH na sua superfície para a ancoragem covalente do complexo de vanádio.  [7] Within the scope of the present invention are vanadium hybrid catalysts, immobilized on a carrier containing -OH groups on their surface for the covalent anchoring of the vanadium complex.
[8] A fórmula geral destes complexos está apresentada em I:  [8] The general formula of these complexes is presented in I:
[Chem. l]  [Chem. l]
Figure imgf000004_0001
Figure imgf000004_0001
[9] Em que n=l a 4;  [9] Where n = 1 to 4;
[10] R1 e R2 são independentes podendo ser diferentes ou iguais e podem ser -H, -X [10] R 1 and R 2 are independently may be different or equal and may be -H, -X
(halogéneo), Cl a C4 alquil linear ou ramificado, -N02, -OH, -OMe, -OEt; (halo), Cl to C4 linear or branched alkyl, -N0 2, -OH, -OMe, -OEt;
[11] A é um material suporte contendo grupos -OH na sua superfície, por exemplo sílica, sílica funcionalizada, alumina, alumina funcionalizada, materiais mesoporosos entre outros.  [11] A is a carrier material containing -OH groups on its surface, for example silica, functionalized silica, alumina, functionalized alumina, mesoporous materials among others.
[12] Um outro aspecto da presente invenção é a aplicação destes complexos de vanádio como catalisadores na reacção de oxidação de cicloalcanos utilizando dioxigénio ou ar como agente oxidante. [12] Another aspect of the present invention is the application of these vanadium complexes as catalysts in the oxidation reaction of cycloalkanes using dioxygen or air as oxidizing agent.
[13] Surpreendentemente verificou-se que estes complexos imobilizados, quando  [13] Surprisingly, it was found that these immobilized complexes, when
aplicados na reacção de oxidação de cicloalcanos com dioxigénio, proporcionam elevadas conversões e selectividade para os produtos, nomeadamente álcoois e cetonas cíclicas. Também de forma surpreendente verificou-se que o nível de conversão destes catalisadores é superior quando estes são aplicados imobilizados (catálise heterogénea) do que quando aplicados como catalisadores homogéneos. Estes catalisadores apresentam também a vantagem de não necessitarem a utilização de solvente no processo de oxidação e assim permitirem uma fácil separação dos produtos, sendo simultaneamente recicláveis e reutilizáveis sem perda significativa da sua actividade.  applied in the oxidation reaction of cycloalkanes with dioxygen, provide high conversions and selectivity for the products, namely cyclic alcohols and ketones. Also surprisingly it has been found that the conversion level of these catalysts is higher when they are applied immobilized (heterogeneous catalysis) than when applied as homogeneous catalysts. These catalysts also have the advantage that they do not require the use of solvent in the oxidation process and thus allow easy separation of the products and are both recyclable and reusable without significant loss of their activity.
[14] No processo desenvolvido, obteve-se uma conversão global entre 20 e 25 % para os catalisadores híbridos, que pode ser ainda melhorada pela adição de ácidos  [14] In the process developed, overall conversion between 20 and 25% was achieved for the hybrid catalysts, which can be further improved by the addition of acids
heterocíclicos com uma conversão entre 30 e 35 , e com uma elevada selectividade global (álcoois cíclicos + cetonas cíclicas) que pode atingir 97%.  heterocyclic compounds having a conversion of from 30 to 35, and having a high overall selectivity (cyclic alcohols + cyclic ketones) which may reach 97%.
Breve descrição das figuras  Brief description of the figures
[15] Fig.1 - Fórmula geral I dos complexos de vanádio imobilizados em que n=l a 4, R1 e R2 são independentes podendo ser diferentes ou iguais e podem ser -H, -X (halogéneo), Cl a C4 alquil linear ou ramificado, -N02, -OH, -OMe, -OEt e A é um material de suporte com grupos -OH na sua superfície. [15] Fig.1 - general Formula I of the vanadium complex immobilized la wherein n = 4, R 1 and R 2 are independent and may be the same or different and may be -H, -X (halogen), Cl to C4 alkyl linear or branched, -N0 2, -OH, -OMe, -OEt and a is a support material with -OH groups on their surface.
[16] Fig. 2 - Fórmula geral da reacção de oxidação de cicloalcanos a álcoois e cetonas cíclicas.  [16] Fig. 2 - General formula of the oxidation reaction of cycloalkanes to cyclic alcohols and ketones.
[17] Fig. 3 - Fórmula estrutural dos catalisadores híbridos II e III.  [17] Fig. 3 - Structural Formula of Hybrid Catalysts II and III.
Descrição detalhada da invenção  Detailed description of the invention
[18] De seguida far-se-á referência a modos de realização preferencial da invenção. Estes não devem ser interpretados como limitativos da invenção, mas sim exemplificativos desta sem limitar o seu âmbito de protecção e/ou aplicação.  [18] Reference will now be made to preferred embodiments of the invention. These should not be construed as limiting the invention, but rather exemplary thereof without limiting its scope of protection and / or application.
[19] Numa forma de realização encontram-se novos catalisadores híbridos à base de  [19] In one embodiment there are novel hybrid catalysts based on
complexos de vanádio com alcoxisilanos coordenados por átomos de nitrogénio e oxigénio (-N, -O) e suportados por ancoragem covalente à sílica de fórmula geral II e III. [Chem.2] Vanadium complexes with alkoxysilanes coordinated by nitrogen and oxygen (N, -O) atoms and supported by covalent anchoring to the silica of formula II and III. [Chem.2]
Figure imgf000006_0001
Figure imgf000006_0001
Catalisador Híbrido- II Catalisador Híbrido- III  Hybrid Catalyst - II Hybrid Catalyst - III
[20] Estes novos catalisadores foram ancorados à sílica, no entanto é possível imobilizar estes complexos na superfície de outros materiais naturais ou funcionalizados que contenham grupos -OH na sua superfície, entre eles sílica, sílica funcionalizada, alumina, alumina funcionalizada, materiais mesoporosos e outros.  [20] These new catalysts have been anchored to silica, however it is possible to immobilize these complexes on the surface of other natural or functionalized materials containing -OH groups on their surface, among them silica, functionalized silica, alumina, functionalized alumina, mesoporous materials and others.
[21] Foi utilizado o método de impregnação via húmida para a modificação da superfície da sílica. Cada complexo de vanádio (50 mg) foi dissolvido separadamente em tolueno seco (50 mL) e a respectiva solução adicionada à sílica (1000 mg) para a preparação do catalisador híbrido suportado. As misturas foram aquecidas durante a noite sob refluxo com a eliminação dos álcoois e após algum tratamento foram obtidos os catalisadores híbridos de vanádio.  [21] The wet impregnation method was used for the modification of the silica surface. Each vanadium complex (50 mg) was dissolved separately in dry toluene (50 mL) and the solution added to the silica (1000 mg) for the preparation of the supported hybrid catalyst. The blends were heated overnight under reflux with the removal of the alcohols and after some treatment the hybrid vanadium catalysts were obtained.
[22] Noutro aspecto da presente invenção encontra-se um processo de oxidação selectiva de cicloalcanos, como por exemplo ciclohexano e ciclopentano, com elevadas taxas de conversão utilizando como catalisadores os complexos de vanádio híbridos.  [22] In another aspect of the present invention there is a selective oxidation process of cycloalkanes such as cyclohexane and cyclopentane with high conversion rates using the hybrid vanadium complexes as catalysts.
[23] Estes catalisadores exibem uma conversão e selectividade melhorada nos processos de oxidação do ciclohexano para os correspondentes ciclohexanol e ciclohexanona, com dioxigénio, sob condições de reacção moderadas, quer na presença quer na ausência de ácidos heterocíclicos.  [23] These catalysts exhibit improved conversion and selectivity in the oxidation processes of cyclohexane to the corresponding cyclohexanol and cyclohexanone with dioxygen under moderate reaction conditions both in the presence and absence of heterocyclic acids.
[24] As reacções foram realizadas num micro reactor descontínuo para elevadas pressões, com 40 cm3 de capacidade, com temperaturas entre 100 e 200°C, pressões entre 5 e 25 bar e tempos de reacção entre 180 e 1440 minutos. Este reactor dispunha de uma entrada para gás e de um medidor de pressão. A medida da temperatura interna e respectivo controlo foi obtida por um termopar e por um controlador on/off. As reacções de oxigenação foram realizadas neste reactor, adicionando o catalisador de vanádio suportado ao cicloalcano, (por exemplo o ciclohexano). O reactor foi depois fechado, o ar removido sob vácuo e o 02 introduzido até à pressão pretendida. O gás utilizado habitualmente foi o oxigénio, contudo podem ser utilizados o ar, ar enriquecido com oxigénio puro e oxigénio diluído com gás inerte como Ar, N2 ou He. [24] The reactions were carried out in a high pressure discontinuous micro reactor with 40 cm 3 capacity, temperatures between 100 and 200øC, pressures between 5 and 25 bar and reaction times between 180 and 1440 minutes. This reactor had a gas inlet and a pressure gauge. The measurement of the internal temperature and its control was obtained by a thermocouple and an on / off controller. The oxygenation reactions were carried out in this reactor by adding the supported vanadium catalyst to the cycloalkane, (for example cyclohexane). The reactor was then closed, the air removed under vacuum and the 0 2 introduced until the desired pressure. The usual gas used was oxygen, however, air, air enriched with pure oxygen and oxygen diluted with inert gas such as Ar, N 2 or He can be used.
[25] Após as reacções de oxidação os catalisadores apresentam uma cor castanha clara. No final das reacções o catalisador foi separado da solução e lavado várias vezes com acetona. Os catalisadores podem ser regenerados para uso posterior, através de aquecimento a 60 °C, numa atmosfera de ar estático, num forno. Verificou-se que um catalisador utilizado durante 1440 minutos de reacção e regenerado posteriormente, apresentava praticamente o mesmo poder catalítico, não tendo ocorrido perda de vanádio, apesar da sua cor ter mudado de verde para castanho. [25] After the oxidation reactions the catalysts have a light brown color. At the end of the reactions the catalyst was separated from the solution and washed several times with acetone. The catalysts may be regenerated for later use, by heating at 60øC, in a static air atmosphere, in a furnace. A catalyst used for 1440 minutes of reaction and regenerated thereafter was found to have substantially the same catalytic power, with no loss of vanadium occurring, although its color changed from green to brown.
[26] A análise dos produtos de reacção foi realizada da seguinte forma: misturou-se ci- clopentanol, como padrão interno, com o produto final. Esta mistura foi injectada (0.5 μί) num GC (a 240°C, He como gás de arrasto). A temperatura inicial da coluna foi de 100°C durante o primeiro minuto, depois aumentada em 10°C/min até 180°C e mantida nesta temperatura durante 1 min. A confirmação dos produtos de reacção foi posteriormente efectuada através da análise por GC-MS. O grau de conversão e o coeficiente de selectividade dos produtos do processo de oxidação foram calculados a partir dos resultados obtidos nestas análises (com o método do padrão interno). Os valores ilustrativos foram calculados para a conversão em fracção molar produto/ substrato. [26] Analysis of the reaction products was performed as follows: Cyclopentanol was blended as an internal standard with the final product. This mixture was injected (0.5 μl) into a GC (at 240 ° C, He as the trailing gas). The initial column temperature was 100øC for the first minute, then increased at 10øC / min to 180øC and held at this temperature for 1 min. Confirmation of the reaction products was further effected by GC-MS analysis. The degree of conversion and the selectivity coefficient of the products of the oxidation process were calculated from the results obtained in these analyzes (using the internal standard method). Illustrative values were calculated for conversion into product / substrate molar fraction.
[27] A quantidade de catalisador híbrido aplicado é fornecida em percentagem molar relativamente ao ciclohexano, não sendo necessária a utilização de solventes durante a reacção.  [27] The amount of hybrid catalyst applied is given in mole percent relative to cyclohexane, and no use of solvents is required during the reaction.
[28] O processo de oxidação selectiva de cicloalcanos com os catalisadores de vanádio híbridos podem ainda ser complementados pela utilização de co-catalisadores do tipo ácidos heterocíclicos tais como o ácido picolínico, o ácido 2,6-pirazinodicarboxílico, o ácido 5-hidroxi-2-pirazinocarboxílico, o ácido 5-metil-2-pirazinocarboxílico, o ácido 3-aminopirazino-2-carboxílico e o ácido 2-pirazinocarboxílico.  [28] The selective oxidation process of cycloalkanes with the hybrid vanadium catalysts can further be complemented by the use of heterocyclic acid type cocatalysts such as picolinic acid, 2,6-pyrazinedicarboxylic acid, 5-hydroxy- 2-pyrazinecarboxylic acid, 5-methyl-2-pyrazinecarboxylic acid, 3-aminopyrazine-2-carboxylic acid and 2-pyrazinecarboxylic acid.
[29] Numa forma de realização preferencial do processo, o oxigénio é um reagente  [29] In a preferred embodiment of the process, oxygen is a reagent
limitante, pelo que o catalisador ainda está activo no final da reacção e pode ser reutilizado. Na verdade, após as reacções de oxidação do ciclohexano sob condições ideais, o reactor foi despressurizado, introduzido mais oxigénio até perfazer 10 bar e a reacção foi continuada por mais tempo. O rendimento global aumentou então de 10% relativamente à primeira etapa mostrando que o sistema ainda apresenta um  limiting agent, whereby the catalyst is still active at the end of the reaction and can be reused. In fact, after the oxidation reactions of cyclohexane under ideal conditions, the reactor was depressurised, more oxygen was introduced to 10 bar and the reaction was continued for a longer time. The overall yield then increased by 10% over the first step showing that the system still has a
considerável efeito catalítico após o consumo do primeiro oxigénio. O catalisador híbrido sólido pode ser utilizado para posteriores reacções de oxidação simplesmente pela adição de mais 02, mesmo sem o isolar e reactivar. Este resultado indica que a utilização de um reactor contínuo aumenta o rendimento global. catalytic effect after consumption of the first oxygen. The solid hybrid catalyst can be used for further oxidation reactions simply by adding more 0 2 , even without isolating and reactivating it. This result indicates that the use of a continuous reactor increases the overall yield.
[30] Noutra forma de realização preferencial, após a utilização, o catalisador pode ser reactivado e reciclado sob a acção de calor. Para verificar que este catalisador reciclado mantinha o poder catalítico, foram efectuados testes nas mesmas condições de reacção anteriores. A presença de vanádio no catalisador suportado foi testada por ICP (inductive couple plasma analyses) mostrando que apenas ocorreu uma pequena perda de vanádio. Antes da primeira utilização determinou-se 0,22% de vanádio (em massa), quantidade que diminuiu para 0,19% após a utilização (720 minutos) e respectiva regeneração. Em regenerações posteriores não foi detectada diminuição da quantidade de vanádio. Os testes mostraram que o catalisador híbrido regenerado possui uma capacidade catalítica inalterada, com um rendimento global de conversão de 21% (sob as mesmas condiçãs para 720 minutos). [30] In another preferred embodiment, after use, the catalyst can be reactivated and recycled under the action of heat. To verify that this recycled catalyst maintained the catalytic power, tests were performed under the same reaction conditions as above. The presence of vanadium on the supported catalyst was tested by ICP (inductive couple plasma analyzes) showing that only a small loss of vanadium occurred. Before the first use 0.22% of vanadium (by mass) was determined, which decreased to 0.19% after use (720 minutes) and its regeneration. In subsequent regenerations no decrease in the amount of vanadium was detected. Tests have shown that the regenerated hybrid catalyst has an unchanged catalytic capacity, with an overall conversion yield of 21% (under the same conditions for 720 minutes).
[31] Após o processo de oxidação, as análises da mistura formada foram efectuadas por cromatografia gasosa (GC) e por cromatografia gasosa - espectrometria de massa (GC-MS) para análises quantitativas (com o método do padrão interno). O grau de conversão e o coeficiente de selectividade foram calculados a partir dos resultados.  After the oxidation process, analyzes of the mixture formed were performed by gas chromatography (GC) and by gas chromatography - mass spectrometry (GC-MS) for quantitative analysis (using the internal standard method). The degree of conversion and the selectivity coefficient were calculated from the results.
[32] Exemplo 1 - Síntese do complexo II  [32] Example 1 - Synthesis of complex II
Uma solução de sal de vanádio (VO(C5H702)2 , 2xl03 mol - 4xl03 mol) em THF (5-50 mL) foi adicionada, sob agitação constante, a uma quantidade equimolar de bis(salicilideno amino-3-propil)amina com o ligando 3-iodopropil trialcoxisilano (2x103 mol - 4x103 mol) em THF (10-55 mL). A mistura foi aquecida sob refluxo. A solução final formada foi concentrada e após a adição de um alcano precipita um sólido verde. Este sólido foi separado por filtração, lavado com o alcano e seco sob vácuo para obter o complexo II de vanádio (87% de rendimento). Este complexo é solúvel na maior parte dos solventes orgânicos polares. A vanadium salt solution (VO (C 5 H 7 0 2) 2, 2xl0 3 mol - 4xl0 3 mol) in THF (5-50 mL) was added under constant agitation to an equimolar amount of bis (salicylidene amino -3-propyl) amine with 3-iodopropyl trialkoxysilane ligand (2x10 3 mol - 4x10 3 mol) in THF (10-55 mL). The mixture was heated under reflux. The final solution formed was concentrated and after addition of an alkane precipitated a green solid. This solid was separated by filtration, washed with the alkane and dried under vacuum to obtain the vanadium complex II (87% yield). This complex is soluble in most polar organic solvents.
[33] Foi utilizado o método de impregnação via húmida para a modificação da superfície da Si02, obtendo uma sílica funcionalizada (1.0 g) pelo complexo de vanádio (50 mg) ligado covalentemente. Este sólido foi filtrado, lavado várias vezes com álcool e seco numa estufa. Após a secagem verificamos que existiam 45 mg de catalisador II por grama de Si02 funcionalizada, constituindo um catalisador suportado híbrido. [33] The wet impregnation method was used for the modification of the SiO 2 surface, obtaining a functionalized silica (1.0 g) by the covalently bound vanadium complex (50 mg). This solid was filtered, washed several times with alcohol and dried in an oven. After drying, we verified that there were 45 mg of catalyst II per gram of functionalized SiO 2 , constituting a hybrid supported catalyst.
[34] Exemplo 2 - Síntese do Complexo III  [34] Example 2 - Synthesis of Complex III
Uma solução de sal de vanádio (VO(C5H702)2 , 0,5xl03 mol - 3xl03 mol) em THF (5-50 mL) foi adicionada, sob agitação constante, a uma quantidade equimolar de bis(cloro-salicilideno amino-3-propil)amina com o ligando 3-iodopropil trialcoxisilano (0,5x103 mol - 3x103 mol) em THF (10-55 mL). A mistura foi aquecida sob refluxo. A solução final formada foi concentrada e após a adição de um alcano precipita um sólido verde. Este sólido foi separado por filtração, lavado com o alcano e seco sob vácuo para obter o complexo III de vanádio (86% de rendimento). Este complexo é solúvel na maior parte dos solventes orgânicos polares. A vanadium salt solution (VO (C 5 H 7 0 2) 2, 0,5xl0 3 mol - 3xl0 3 mol) in THF (5-50 mL) was added under constant agitation to an equimolar amount of bis ( chloro-salicylidene amino-3-propyl) amine with 3-iodopropyl trialkoxysilane ligand (0.5x10 3 mol - 3x10 3 mol) in THF (10-55 mL). The mixture was heated under reflux. The final solution formed was concentrated and after addition of an alkane precipitated a green solid. This solid was separated by filtration, washed with the alkane and dried under vacuum to obtain vanadium complex III (86% yield). This complex is soluble in most polar organic solvents.
[35] Foi utilizado o método de impregnação via húmida para a modificação da superfície da Si02, obtendo uma sílica funcionalizada (1.0 g) pelo complexo de vanádio (50 mg) ligado covalentemente. Este sólido foi filtrado, lavado várias vezes com álcool e seco numa estufa. Após a secagem verificamos que existiam 41 mg de catalisador III por grama de Si02 funcionalizada, constituindo um catalisador suportado híbrido. [35] The wet impregnation method was used for the modification of the SiO 2 surface, obtaining a functionalized silica (1.0 g) by the covalently linked vanadium complex (50 mg). This solid was filtered, washed several times with alcohol and dried in an oven. After drying, we verified that there were 41 mg of catalyst III per gram of functionalized SiO 2 , constituting a hybrid supported catalyst.
[36] Exemplo 3 - Oxidação de ciclohexano/catalisador híbrido II  [36] Example 3 - Oxidation of Cyclohexane / Hybrid Catalyst II
Num micro reactor do tipo oscilante com 40 mL de capacidade, equipado com medidor de pressão e entrada de gás, foram carregados 27.8 mmol de ciclohexano e 30 mg de catalisador híbrido II. A temperatura do interior do reactor foi medida com um termopar. O reactor foi fechado e o ar removido por uma bomba de vácuo, tendo sido usado ainda uma purga de N2. A temperatura do reactor foi estabelecida a 140°C e o 02 foi introduzido até à pressão de 10 bar. O tempo total de reacção foi de 720 minutos. Após a reacção, o catalisador foi separado da mistura reaccional e lavado com ace- tonitrilo. A análise da mistura reaccional indica uma conversão de ciclohexano de 20.3% com 67.0% e 21.1% de ciclohexanol e ciclohexanona respectivamente. In a 40 mL capacity oscillating reactor equipped with a gas pressure and gas meter, 27.8 mmol cyclohexane and 30 mg Hybrid II catalyst were charged. The temperature inside the reactor was measured with a thermocouple. The reactor was closed and the air removed by a vacuum pump, further using a N 2 purge. The reactor temperature was set at 140 ° C and 2 0 was introduced to a pressure of 10 bar. The total reaction time was 720 minutes. After the reaction, the catalyst was separated from the reaction mixture and washed with acetonitrile. Analysis of the reaction mixture indicates a conversion of cyclohexane of 20.3% with 67.0% and 21.1% of cyclohexanol and cyclohexanone respectively.
[37] Exemplo 4 - Oxidação de ciclohexano/catalisador híbrido III  [37] Example 4 - Oxidation of Cyclohexane / Hybrid Catalyst III
Foram carregados 27.8 mmol de ciclohexano e 30 mg de catalisador híbrido III nas mesmas condições de reacção do exemplo 3. Após a reacção, o catalisador foi separado da mistura reaccional e lavado com acetonitrilo. A análise da mistura reaccional indica uma conversão de ciclohexano de 24.5% com 74% e 23.4% de ciclohexanol e ciclohexanona respectivamente.  27.8 mmol of cyclohexane and 30 mg of hybrid III catalyst were loaded under the same reaction conditions as in Example 3. After the reaction the catalyst was separated from the reaction mixture and washed with acetonitrile. Analysis of the reaction mixture indicates a conversion of cyclohexane of 24.5% with 74% and 23.4% of cyclohexanol and cyclohexanone respectively.
[38] Exemplo 5 Oxidação de ciclohexano /catalisador híbrido + ácido heteroaromático  [38] Example 5 Oxidation of cyclohexane / hybrid catalyst + heteroaromatic acid
Foram carregados 27.8 mmol de ciclohexano e 30 mg de catalisador híbrido II ou III, com 8.1 x IO 5 mol de um ácido carboxílico (ácido picolínico ou ácido 2,6- pirazinadicarboxílico ou ácido 5-hidróxi-2-pirazinocarboxílico ou ácido 27.8 mmol of cyclohexane and 30 mg of hybrid catalyst II or III were charged with 8.1 x 10 5 mol of a carboxylic acid (picolinic acid or 2,6-pyrazinedicarboxylic acid or 5-hydroxy-2-pyrazinecarboxylic acid or
5-metil-2-pirazinocarboxílico ou ácido 3-aminopirazino-2-caroxílico ou ácido  5-methyl-2-pyrazinecarboxylic acid or 3-aminopyrazine-2-carboxylic acid or
2-pirazinocarboxílico) como co-catalisador, nas mesmas condições de reacção do exemplo 3.  2-pyrazinecarboxylic acid) as co-catalyst under the same reaction conditions as in Example 3.
[39] Verifica-se que o ácido 2-pirazinocarboxílico (APC) é o melhor co-catalisador do processo, aumentando a conversão global em cerca de 10% quer para o catalisador II quer para o III. A adição de mais APC (até obter uma razão APC: catalisador híbrido II ou III de 2: 1) leva a uma aumento considerável da conversão para ciclohexanol + ciclohexanona.  [39] 2-Pyrazinecarboxylic acid (APC) is found to be the best cocatalyst in the process, increasing the overall conversion by about 10% for both catalyst II and III. Addition of more APCs (until an APC ratio of 2: 1 hybrid catalyst II or III) leads to a considerable increase in conversion to cyclohexanol + cyclohexanone.
[40] Exemplo 6 - Oxidação de ciclohexano/catalisador homogéneo II ou III  [40] Example 6 - Oxidation of Cyclohexane / Homogeneous Catalyst II or III
A reacção foi efectuada da mesma forma que no exemplo 3, com o catalisador de vanádio II ou III não suportado. A análise da mistura reaccional final indica para o catalisador II uma conversão global de 5.2%, com uma selectividade de 65.4% e 20.2% para o ciclohexanol e ciclohexanona respectivamente. O catalisador III fornece uma conversão global de 6.6%, com uma selectividade de 66.4% e 19.3% para o ciclohexanol e ciclohexanona respectivamente.  The reaction was carried out in the same manner as in example 3, with the unsupported vanadium II or III catalyst. Analysis of the final reaction mixture indicated for Catalyst II an overall conversion of 5.2%, with a selectivity of 65.4% and 20.2% for cyclohexanol and cyclohexanone respectively. Catalyst III provides an overall conversion of 6.6%, with a selectivity of 66.4% and 19.3% for cyclohexanol and cyclohexanone respectively.
[41] Estes resultados indicam que as novas espécies híbridas suportadas de vanádio  [41] These results indicate that the new hybrid species supported by vanadium
(complexos trialcoxisililvanato ligados covalentemente à sílica) são catalisadores mais activos do que as espécies equivalentes não suportadas. (trialkoxysililvanate complexes covalently bound to silica) are more assets than the equivalent unsupported species.
[42] Exemplo 7 - Oxidação de ciclohexano / catalisador híbrido II + Agente oxidante: Ar [42] Example 7 - Oxidation of cyclohexane / hybrid catalyst II + Oxidizing agent: Air
O processo de oxidação foi executado da mesma forma que no exemplo 3 excepto pelo uso de ar em vez de oxigénio. A análise da mistura reaccional indicou uma conversão global de ciclohexano de 4.5% com uma selectividade de 67.2% e 19.3% em ciclohexanol e ciclohexanona, respectivamente.  The oxidation process was performed in the same manner as in Example 3 except for the use of air instead of oxygen. Analysis of the reaction mixture indicated an overall cyclohexane conversion of 4.5% with a selectivity of 67.2% and 19.3% in cyclohexanol and cyclohexanone, respectively.

Claims

Claims Claims
Catalisadores híbridos de vanádio caracterizados por apresentarem a fórmula geral I:  Hybrid vanadium catalysts characterized by the general formula I:
[Chem.3]  [Chem. 3]
Figure imgf000011_0001
Figure imgf000011_0001
em que n=l a 4; wherein n = 1 to 4;
R1 e R2 são independentes podendo ser diferentes ou iguais e podem ser -H, -X (halogéneo), Cl a C4 alquil linear ou ramificado, -N02, -OH, - OMe, -OEt e; A é um material suporte com grupos funcionais -OH na sua superfície. R 1 and R 2 are independent and may be the same or different and may be -H, -X (halogen), Cl to C4 linear or branched alkyl, -N0 2, -OH, - OMe, -OEt and; A is a carrier material with functional groups -OH on its surface.
Catalisadores híbridos de vanádio de acordo com a reivindicação 1, caracterizados por terem a fórmula geral II ou III:  Vanadium hybrid catalysts according to claim 1, characterized in that they have the general formula II or III:
[Chem.4] [Chem. 4]
Figure imgf000011_0002
Figure imgf000011_0002
Catalisador Híbrido- II Catalisador Híbrido- III  Hybrid Catalyst - II Hybrid Catalyst - III
Catalisadores híbridos de vanádio de acordo com as  Hybrid vanadium catalysts according to the
reivindicações anteriores caracterizados por o material suporte ser sílica funcionalizada.  The foregoing claims are that the carrier material is functionalized silica.
Processo de oxidação de cicloalcanos caracterizado por utilizar os complexos de vanádio de fórmula geral I como catalisadores. Processo de oxidação de cicloalcanos de acordo com a reivindicação 4, caracterizado por a reacção de oxidação utilizar oxigénio ou ar como agente oxidante. Process for the oxidation of cycloalkanes characterized in that the vanadium complexes of general formula I are used as catalysts. Process for the oxidation of cycloalkanes according to claim 4, characterized in that the oxidation reaction uses oxygen or air as the oxidizing agent.
Processo de oxidação de cicloalcanos de acordo com a reivindicação 5, caracterizado por a pressão estar compreendida entre 5 e 25 bar e a temperatura entre 100 e 200 °C. Process for the oxidation of cycloalkanes according to claim 5, characterized in that the pressure is between 5 and 25 bar and the temperature between 100 and 200 ° C.
Processo de oxidação de cicloalcanos de acordo com a reivindicação 6, caracterizado por o processo de oxidação ocorrer a uma pressão de oxigénio 10 bar e à uma temperatura de 140 °C. Processo de oxidação de cicloalcanos de acordo com a reivindicação 7, caracterizado por o catalisador poder ser regenerado por aquecimento e reutilizado. Process for the oxidation of cycloalkanes according to claim 6, characterized in that the oxidation process takes place at a pressure of oxygen 10 bar and at a temperature of 140 ° C. Process for the oxidation of cycloalkanes according to claim 7, characterized in that the catalyst can be regenerated by heating and reused.
Processo de oxidação de cicloalcanos de acordo com a reivindicação 7, caracterizado por poder utilizar-se um ácido heterocíclico como promotor da reacção de oxidação, preferencialmente o ácido picolínico, o ácido 2,6-pirazinodicarboxílico, o ácido 5-hidroxi-2-pirazinocarboxílico, o ácido Process for the oxidation of cycloalkanes according to claim 7, characterized in that a heterocyclic acid can be used as promoter of the oxidation reaction, preferably picolinic acid, 2,6-pyrazinedicarboxylic acid, 5-hydroxy-2-pyrazinecarboxylic acid , the acid
5-metil-2-pirazinocarboxílico, o ácido 5-methyl-2-pyrazinecarboxylic acid,
3-aminopirazino-2-carboxílico e/ou o ácido 3-aminopyrazine-2-carboxylic acid and / or
2-pirazinocarboxílico. 2-pyrazinecarboxylic acid.
Processo de oxidação de cicloalcanos de acordo com as reivindicações 8 e 9, caracterizado por a selectividade do processo ser superior a 85% para os produtos cetonas cíclicas e álcoois cíclicos, preferencialmente superior a 95 %.  Process for the oxidation of cycloalkanes according to claims 8 and 9, characterized in that the process selectivity is greater than 85% for cyclic ketone and cyclic alcohols, preferably higher than 95%.
Processo de oxidação de cicloalcanos de acordo com a as reivindicações 4 a 10, caracterizado por o cicloalcano ser ci- clohexano ou ciclopentano. The oxidation process of cycloalkanes according to claims 4 to 10, characterized in that the cycloalkane is cyclohexane or cyclopentane.
Processo de oxidação de cicloalcanos de acordo com as reivindicações 4 a 11, caracterizado por utilizar-se o complexo II ou III como catalisador.  Process for the oxidation of cycloalkanes according to claims 4 to 11, characterized in that the complex II or III is used as the catalyst.
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Citations (8)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
GB777087A (en) 1954-05-12 1957-06-19 Du Pont Improvements in or relating to the oxidation of cyclohexane
US3530185A (en) 1966-08-08 1970-09-22 Du Pont Oxidation process
US5767320A (en) 1995-09-29 1998-06-16 Council Of Scientific & Industrial Research Process for the oxidation of cyclohexane to a mixture of cyclohexanone and cyclohexanol
WO2000053550A1 (en) 1999-03-10 2000-09-14 E.I. Du Pont De Nemours And Company Hydroperoxide decomposition process
WO2003059512A1 (en) * 2002-01-04 2003-07-24 Rhodia Chimie Immobilized catalyst for heterogeneous catalysis
US20040092767A1 (en) 2002-11-07 2004-05-13 Chu Luis A. Process for the production of an aqueous solution of adipic acid, hydroxyhexanoic acid and oligomers thereof
US7081552B2 (en) 2004-08-17 2006-07-25 Solutia Inc. Catalysts for cycloalkanes oxidation and decomposition of cycloalkyl hydroperoxide
US7166751B2 (en) 2005-03-30 2007-01-23 Sumitomo Chemical Company, Limited Method for manufacturing cycloalkanol and/or cycloalkanone

Patent Citations (8)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
GB777087A (en) 1954-05-12 1957-06-19 Du Pont Improvements in or relating to the oxidation of cyclohexane
US3530185A (en) 1966-08-08 1970-09-22 Du Pont Oxidation process
US5767320A (en) 1995-09-29 1998-06-16 Council Of Scientific & Industrial Research Process for the oxidation of cyclohexane to a mixture of cyclohexanone and cyclohexanol
WO2000053550A1 (en) 1999-03-10 2000-09-14 E.I. Du Pont De Nemours And Company Hydroperoxide decomposition process
WO2003059512A1 (en) * 2002-01-04 2003-07-24 Rhodia Chimie Immobilized catalyst for heterogeneous catalysis
US20040092767A1 (en) 2002-11-07 2004-05-13 Chu Luis A. Process for the production of an aqueous solution of adipic acid, hydroxyhexanoic acid and oligomers thereof
US7081552B2 (en) 2004-08-17 2006-07-25 Solutia Inc. Catalysts for cycloalkanes oxidation and decomposition of cycloalkyl hydroperoxide
US7166751B2 (en) 2005-03-30 2007-01-23 Sumitomo Chemical Company, Limited Method for manufacturing cycloalkanol and/or cycloalkanone

Non-Patent Citations (13)

* Cited by examiner, † Cited by third party
Title
ANDO, RYUJI ET AL: "Structural characterization of pentadentate salen-type Schiff-base complexes of oxovanadium(IV) and their use in sulfide oxidation", INORGANICA CHIMICA ACTA , 357(4), 1177-1184 CODEN: ICHAA3; ISSN: 0020-1693, 2004, XP002602834 *
APPL. CATAL. A: GEN., vol. 135, 1996, pages L7 - L11
APPL. CATAL. A: GEN., vol. 203, 2000, pages 231
CARRE, FRANCIS ET AL: "X-Ray crystal structures of copper(II) and cobalt(II) complexes with Schiff base ligands. Reactivity towards dioxygen", DALTON TRANSACTIONS , (16), 3211-3215 CODEN: DTARAF; ISSN: 1477-9226, 2003, XP002602835 *
CAT. LETT., vol. 81, 2002, pages 113
J. MOL. CAT. A: CHEM., vol. 239, 2005, pages 96
JOSEPH T ET AL: "Oxidation of adamantane by urea hydroperoxide using vanadium complex anchored onto functionalized Si-MCM-41", JOURNAL OF MOLECULAR CATALYSIS A: CHEMICAL, vol. 207, no. 2, 17 July 2003 (2003-07-17), pages 131 - 137, XP002602837, DOI: 10.1016/S1381-1169(03)00462-X *
JOSEPH T ET AL: "Oxyfunctionalization of limonene using vanadium complex anchored on functionalized SBA-15", JOURNAL OF MOLECULAR CATALYSIS. A, CHEMICAL, ELSEVIER, AMSTERDAM, NL LNKD- DOI:10.1016/J.MOLCATA.2004.12.008, vol. 229, no. 1-2, 29 March 2005 (2005-03-29), pages 241 - 247, XP004736529, ISSN: 1381-1169 *
MISHRA G ET AL: "Novel alkoxysilane pentacoordinate O=V(IV) complexes as supported catalysts for cyclohexane oxidation with dioxygen", APPLIED CATALYSIS A: GENERAL, vol. 384, no. 1-2, 19 June 2010 (2010-06-19), pages 136 - 146, XP002602839, DOI: 10.1016/j.apcata.2010.06.018 *
MISHRA G S ET AL: "Preparation of Heterogeneous Vanadium (VO2+) Catalyst for Selective Hydroxylation of Cyclohexane by Molecular Oxygen", CATALYSIS LETTERS, vol. 81, no. 1-2, July 2002 (2002-07-01), pages 113 - 117, XP002602833, DOI: 10.1023/A:1016076526549 *
SUTRA P ET AL: "Preparation of MCM-41 type silica-bound manganese(III) Schiff-base complexes", CHEMICAL COMMUNICATIONS, vol. 1996, no. 21, 1996, pages 2485 - 2486, XP009139301, DOI: 10.1039/CC9960002485 *
TATSUNO, YOSHITAKA ET AL: "Vanadium-catecholato complexes as reaction intermediates in the vanadium catalyzed oxygenation of catechols", CHEMISTRY LETTERS , (7), 1209-12 CODEN: CMLTAG; ISSN: 0366-7022, 1984, XP002602836 *
TONG J ET AL: "Highly efficient catalysts of chitosan-Schiff base Co(II) and Pd(II) complexes for aerobic oxidation of cyclohexane in the absence of reductants and solvents", JOURNAL OF MOLECULAR CATALYSIS. A, CHEMICAL, ELSEVIER, AMSTERDAM, NL LNKD- DOI:10.1016/J.MOLCATA.2005.01.011, vol. 231, no. 1-2, 20 April 2005 (2005-04-20), pages 197 - 203, XP004775174, ISSN: 1381-1169 *

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