MXPA99001252A

MXPA99001252A - Process for the preparation of compounds of 2-aril-5- (perfluoroalquil) pirrol from n-perfluroalquilmetil chloride compounds) arilimide

Info

Publication number: MXPA99001252A
Application number: MXPA/A/1999/001252A
Authority: MX
Inventors: Venkataraman Kameswaran
Original assignee: American Cyanamidcompany
Priority date: 1998-02-09
Filing date: 1999-02-03
Publication date: 2000-10-01

Abstract

A process for the preparation of 2-aryl-5- (perfluoroalkyl) pyrrole compounds from N- (perfluoroalkylmethyl) arylimidoyl chloride compounds is presented. The 2-aryl-5- (perfluoroalkyl) pyrrole compounds are useful for combating insects and mites, and can also be used to prepare other pesticidal compounds of arrilpirrol. Furthermore, the present invention presents N- (perfluoroalkylmethyl) arylimidoyl chloride compounds which serve as intermediates in the preparation of the arylpyrr

Description

PROCESS FOR THE PREPARATION OF COMPOUNDS OF 2-ARIL-5- (PERFLUOROALQUIL) PIRROL FROM N-CHLORIDE COMPOUNDS (PERFLU? ROALQUILMET! L) ARILIMIDOILO BACKGROUND OF THE INVENTION The 2-aryl-5- (perfluoroalkyl) pyrrole compounds They are useful as insecticide and acaricide agents. In addition, these compounds also serve for the preparation of other insecticidal and acaricidal agents. Specifically, the 2-aryl-5- (perfluoroalkyl) pyrrol compounds are intermediate intermediates for the preparation of arylpyrrole compounds such as chlorphenpyr. Consequently, there is a constant search to discover new and efficient methods for the preparation of 2-aryl-5- (perioiuoroalkyl) pyrrole compounds. U.S. Patent No. 5,198,986 discloses that 2-aryl-5- (tpfluoromethyl) pyrrole compounds can be prepared from N- (substituted benzyl) compounds. -2.2.2-tr? Fluoroacet? M? Doyle. However, certain 2-ar? L-5- (perfluoroalkyl) pyrrole compounds may not be readily prepared from commercially available starting materials employing the aescppto process in US Pat. No. 5,195,986. United States Patents Nos. 5,446,170 and 6,426,225 express that the compounds 2-apl-5- (tpfluoromet?!) P? Rtol can be obtained in four steps from the appropriate aldehyde The processes described in the aforementioned patents they require the use of an aminonitrile intermediate which is obtained by the Strecker synthesis of the indicated aldehyde. However, the use of the Strecker synthesis is not entirely satisfactory because of the waste streams containing cyanide. Consequently, what is needed in the technique is an efficient process for the preparation of 2-ar? L-5- (perfluoroalkyl) pyrrol compounds that do not require REF. 29314 the use of N- (substituted benzyl) -2,2,2-trifluoroacetoimidoyl chloride compounds and avoid the use of Strecker synthesis. SUMMARY OF THE INVENTION The present invention presents an efficient process for the preparation of 2-aryl-5- (perfluoroalkyl) pyrrole compounds having the formula I C) wherein W is hydrogen 0 CmF2m- ?; And it's CN. NO2 or CO2R; R is C1.C4 alkyl. each of m and n is independently an integer of 1, 2. 3, 4, 5, 6, 7 u L is hydrogen or halogen, each of M and Q is independently hydrogen, halogen, CN, NO2, C1.C4 alkyl: C1.C4 haloalkyl: C? .C4 alkoxy. haloalkoxy C1.C4, alkylthio C1.C4; C 1 -C 4 haloalkylthio: C 1 -C 4 alkylsulfinyl. haloalkylsulfipyl C? .C4: alkylsulfonyl Ci. C4 haloalkylsulfonyl C1.C4, "or, when M and Q are in adjacent positions, they can be taken together with the carbon atoms to which they are attached to form a ring in which MQ represents the structure -OCH20-, -OCF2O- or - CH = CH-CH = CH-, Rt. R2 and R3 are independently hydrogen, halogen, NO2, CHO or R2 and R3 can be taken together with the atoms to which they are attached to form a ring in which R2 3 is represented by the structure each of R4. R5 R ^ and R7 is independently hydrogen, halogen, CN or NO2 and X is O or S process which consists of reacting an N- (perfiuoroalqu? Lmet? L) apl? M? Doc? Chloride compound having the structural formula II Cl N F "n * 2 n • '(" I in which A and n are as described above, with a dienophile compound having the structural formula III ? \ Y and (I I I wherein W and Y are as described above and Z is Cl, Br or I, and a base in the presence of a solvent Advantageously, the process of the present invention does not require the use of a compound N- (benzyl) chloride -2,2,2-tr? fucouacetylmidoyl and avoids the use of Strecker synthesis The present invention also presents novel compounds of N- (perfluoroalkylmethyl) arymethyl chloride having the formula structural II: zi) in which n and A are as described above, provided that, when A is unsubstituted phenyl, p-dorophenyl or p-methylphenyl, n is an integer that I is not 1. DETAILED DESCRIPTION OF THE INVENTION The process according to the present invention preferably consists in the reaction of a N- (perfluoroalkyl-imetyl) aryl-methyl compound of the formula II with at least about one molar equivalent. i? preferably about one to four molar equivalents of a dienophile compound of the formula III and at least one molar equivalent, preferably about one to four molar equivalents of a base in the presence of a solvent, preferably in a temperature range from about 5 ° C to 100 ° C to form the compounds 2-ar? L-5-15 (perf? Uoroalkyl) of the formula I On the other hand, compounds of the formula I can be prepared by forming the dienophile compounds of the formula III m situ. This process consists in making reacting an N- (perfluoroalkylmethyl) compound with the formula II with 'preferably about one to four molar equivalents of a a.β-dihalo compound having the structural formula IV wherein W and Y are as described above and 2 is Cl. Br or I, and at least about a molar equivalents, preferably about two to five molar equivalents of a base in the presence of a solvent, preferably in a range of temperatures of about 5 ° C to 100 ° C to form the 2-aryl-5- (perfluoroalkyl) pyrrole compounds of formula I Advantageously, the present invention presents an efficient process for the preparation of 2-aryl-5- compounds (perfluoroalkyl) pyrrol which does not require the use of an N- (substituted benzyl) -2,2.2-tr? fluoroacetmidoyl compound and avoids the use of Strecker synthesis It has been observed with surprise that N- (perfluoroalkylmethane) arylolide compounds of the present invention undergo cyclloadiaon reactions with dienophiles such as 2-chloroacrylonitrile to produce the same pyrrole regioisomen compounds which are obtained by the reaction of isome compounds rich N- (substituted benzyl) -2,2,2-trifluoroacetmidoyl chloride with dienophiles according to the disclosure in U.S. Patent No. 5,145,986 This novel regiochemical result of the pyrrole-forming reaction of the present invention thus offers alternative and potentially more economical ways of producing 2-aryl-5- (perfluoroalkyl) pyrrole compounds from alpha-halide compounds which are suitable starting materials due to their availability. advantage of the present invention is that a wider variety of 2-ar? l-5- (perfluoroalkyl) pyrrol compounds can be prepared from commercially available acid halide compounds. On the contrary, although the process disclosed in U.S. Patent No. 5,145,986 yields 2-aryl-5- (tr? f? uoromet? l) pyrrol compounds from N- (substituted benzyl) chloride compounds. -2.2.2-tpfluoroacet? M? Do? Lo. certain 2-apl-5-rtpfluoromethyl) pyrrole compounds would require starting materials of benzoyl halide by virtue of a lack of commercially available alternative starting materials. Therefore, the present invention presents an improved process for, for example, when the common starting material for the processes of the present invention and from U.S. Patent No. 5,145,986 is "limited to substituted benzoyl halide compounds. due to economic factors including but not limited to commercial availability on an industrial scale, the process of the present invention is considerably more efficient for the preparation of the desired pyrrole compounds, as demonstrated below in the Diagram.

Diagram I PROCESS OF THE INVENTION Step 1 Base CF3CH2NH2. HCL Step 2 PCI Diagram I (continued) U.S. 5,145,986 Step 1 NH.

Step 2 Reduction Step 3 CF2CO2H [CF3CO] 2O or CF3COCI Step 4 r > ~? CN Step 5 Base .Cl The compounds of formula I according to the present invention can be isolated by conventional methods such as dilution of the reaction mixture with water and filtration or alternatively by extraction with a suitable solvent. Suitable extraction solvents include water immiscible solvents. such as ether, ethyl acetate, Toluene, Methylene Chloride, and Other Suitable bases for use in the present invention include tp (AlkylC.sub.Jamines such as t-methylamine tpetilamide.a, t-polypropylamine, t-butylamine, dnsopropylethylamine and the like alkaline metal carbonates such as potassium carbonate and sodium carbonate alkali metal hydroxides such as potassium hydroxide and sodium hydroxide alkali metal acetates such as potassium acetate and sodium acetate and heterocyclic tertiary amines including, but not limited to, 1.8-d? aza? c? c ! or [5 4 0] undec-7-ene (DBU), 1,5-d? azab? c? clo [4 3 0] non-5-ene (DBN) 1 4-d? azab? c? clo [2.2.2] octane, pipdma substituted pipdines such as 2,6-d? Met? Lp? Pd? Na, 2 methylpipdipa, 3-methylpipdine 4-met? Lp? Pd? Na and the like, quinoline and substituted qumoleins. Preferred bases include tp- (alkyl, 1,8-d? Azab? C? Clo [5 4.0] undec-7- ene, 1.5-d? Azab? Cycle [4.3.0] non-5-ene, 1, 4-diazabicyclo- [2.2.2] octane, potassium carbonate and carbonate Sodium Suitable solvents for use in the present invention include, but are not limited to, carboxylic acid amides such as N, N-dimethylformamide. N.N-dimethylacetamide and the like; N-substituted pyrrolidinones such as N-methylpyrrolidinopa and the like; nitrites such as acetonitrile, propionityl and the like, halogenated hydrocarbons such as methylene chloride. chloroform, carbon tetrachloride and the like; ethers such as tetrahydrofuran. dioxane and the like, sulfoxides such as dimethisulfoxide and the like, as well as mixtures thereof. Preferred solvents include the carboxylic acid amides and miniums and mixtures thereof. The N, N-aimeiiformamide and the acetonitoplo as well as the mixtures thereof, are especially suitable for use in the present invention. Examples of halogens according to the aforementioned are chlorine, bromine and yoao. The terms "haloalkyl C1.C4", "haloalkoxy C1.C4". "haloalkylthio C1.C4", "haloalkylsulfinium C1.C4", and "haloalkylsulfonyl C1.C4" are defined as C1.C4 alkyl groups. C 1 -C 4 alkyloxy C 1 -C 4 alkyloxy, C 1 -C 4 alkylsulfinyl or C 1 -C 4 alkylsulfonyl. C replaced with one or more halogen atoms, respectively. The present invention is especially useful for the preparation of compounds of the formula I in which W is hydrogen: Y is CN. n is 1 or 2.

L is hydrogen or halogen and each of M and Q is independently hydrogen, halogen, C1.C4 haloalkyl or C1.C4 haloalkoxy. In particular, the present invention is useful for the preparation of 2- (4-chlorophen? L) -5- (trifluoromethyl) pyrrol-3-carbon? Tplo; 2- (3-5-dichlorophenyl) -5- (trifluoromethyl) pyrrol-3-carbonyl tripe: 2- (3-a-4-aichlorophen-i) -5- (trifluoromethyl) pyrrol-3- carbonitrile and 2- (4-bromophenyl) -5- (trifluoromethyl) pyrrol-3-carbonyl trile, among others. The present invention also relates to novel N- (perfluoroalkylmethyl) apl? M? Doyl chloride compounds having the structural formula II c: in which n is an integer of 1 2. 3. 4 ^ 5, 6, 7 or 8 L is hydrogen or halogen. each of M and Q is independently hydrogen, halogen. CN, N02, C1.C4 alkyl C1.C4 haloalkyl: C1.C4 alkoxy. haloalkoxy C1.C4. alkylthio C? .C4: haloalkylthio C1.C4. alkylsulfinyl C1.C4, haloalkylsulfinyl C1.C4. alkylsulfonyl C? -Chaloalkylsulfonyl C? .C or. when M and Q are in adjacent positions, they can be taken together with the carbon atoms to which they are attached to form a ring in which MQ represents the structure -OCH2O-, -OCF2O- or -CH = CH-CH = CH -; Ri, R2 and 3 are, independently, hydrogen, halogen, NO2, CHO or R2 and R3 can be taken together with the atoms to which they are attached to form a ring in which R2R3 is represented by the structure each of R 4, R 5, and V R 7 is independently hydrogen, halogen, CN or N 0 and X is O or S provided that when A is unsubstituted phenyl p-chlorophenyl or p-methylphenyl, n is an integer other than 1 novel compounds of the formula II preferred of the present invention are those in which L is hydrogen or halogen and each of M and Q is independently hydrogen, halogen, haloalkyl C? -C or haloalkoxy C? .C with the proviso that. when A is unsubstituted phenyl or p-chlorophenyl, n is 2 Among the novel compounds of formula II of particular utility in the present invention are included N- (2,2,2-trifluoroethylene) -3,5-dichlorobenzyl chloride ? doyle; N- (2.2.2-trifluoroethyl) -3,4-dichlorobenzylidene chloride and N- (2,2,2-tpfluoroethyl) -4-bromobenzyldoyl chloride, among others.

The initial N- (perfluoroalkylmethyl) arylimidoxyl chloride compounds of the formula II can be prepared, according to that illustrated in Diagram 1, by reacting an acid halide compound of the structural formula V with a perfluoroalkylmethylamine or a salt of perfluoroalkylmethylamine acid addition of structural formula VI in the presence of a base 'to form a benzamide compound having structural formula VII, and reacting the benzamide compound with (1) phosphorus pentachloride or (2) phosgene followed by NN -dirrrethylformamide (DMF).

DIAGRAM II O A ^ Xa + HX2. H2NCH2 CnF2n * 1 (v) (VI) (X, = Cl or Br) (X2 = Cl or Br) i I Base (Vil) 1) PCI5 or 2) phosgene / DMF (I I) On the other hand, the N- (perfluoroalkylmethyl) arylimidoyl chloride compounds of the formula II can be prepared, as illustrated in the Diagram. III, by means of the isomepzaaon of a N- (arylmethyl) perfluoroalkyl chloride compound with a tertiary amine such as triethylamine at an elevated temperature according to the procedures described in US Pat.

Chemistry Letters. P. 1463-1464 (1983). The N- (aryl-methyl) perfluoroalkylformate chloride compounds can be prepared according to the methods disclosed in U.S. Patent No. 5,145,986 and in Chemistry Letters, p. 1463-1464 (1983). DIAGRAM III (c2? s), N Cl C r_. 2 n * 1 (II) The initial dienophilic compounds of formula III are known in the art and can be prepared using conventional procedures. The compounds of formulas III and IV in which W is CmF2.t, *? they can be prepared according to the disclosed processes in U.S. Patent No. 5 068 390. The compounds of the formula I are useful for controlling insect pests and mites. In addition, the compounds of the formula I can be used to prepare other insecticidal and acaricidal arylpyrrole agents having the structural formula VIII J (VII I) in which Y is CN. N02 or C02R; R is C1-C4 alkyl; n is an integer of 1, 2, 3, 4, 5 6, 7 or 8; L is hydrogen or halogen; each of M and Q is independently hydrogen, halogen, CN, NO2, C1.C4 alkyl, C1.C4 haloalkyl; C1.C4 alkoxy; C1-C4 haloalkoxy, C 1 -C 4 alkylthio. haloalkylthio C1.C4; C 1 -C 4 alkylsulfinyl; haloalkylsulfinyl alkylsulfonyl C1. C. haloalkylsulfonyl C? .C4; or, when M and Q are in adjacent positions, they can be taken together with the carbon atoms to which they are attached to form a ring in which Q represents the structure -OCH2O-, -OCF20- or -CH = CH-CH = CH-: each of R1 t R2 and R3 is independently hydrogen, halogen, NO2, or R2 and R3 can be taken together with the atoms to which they are attached to form a ring in which R2R3 is represented by the structure each of R4, R5, R6 and R7 is independently hydrogen, halogen, CN or N02. X is O or S; Hal is a halogen atom and J is hydrogen or Ci-Cβ alkoxymethyl- Advantageously, the arylpyrrole compounds of the formula VIII can be prepared by a process consisting of a) reacting an N- (perfluoroalkylmethyl) arylimidoyl chloride compound of formula II with a dienophile compound having the structural formula IX (IX) wherein Y is as described above and Z is Cl, Br or I, and a base in the presence of a solvent to form a 2.apl-5- (perfluoroalkyl) pyrrole compound having the structural formula X b) halogenating the compound of the formula X to form the compound arylpyrrole of the formula VIII in which J is hydrogen and c) optionally, alkoxymethylating the compound of the formula VIII in which J is hydrogen to form the compound arylpyrrole of the formula VIII wherein J is alkoxymethyl Ci-Ce. On the other hand, the arylpyrrole compounds of the formula VIII can be prepared by a process consisting of: a) the reaction of an N- (perfiuoroalkylmethyl) arylimidoyl chloride compound of the formula II with an α, β-dihalo compound having the structural formula XI 2 V j j HC- • CH 1 | 1 H z (X I) wherein Y is as described above and Z is Cl. Br or I, and at least about two molar equivalents of a base in the presence of a solvent to form a 2.aril-5- (perfluoroalkyl) pyrrole compound which has the structural formula X (X) b) the halogenation of the compound of the formula X to form the aplpyrrole compound of the formula VIII in which J is hydrogen and c) optionally, the methoxymethylatop the compound of the formula VIII in which J is hydrogen to form the arylpyrrole compound of the Formula VIII in which J is alkoxymethyl Ci.Cß. The present invention is especially useful for the preparation of arylpyrrole compounds of the formula VIII in which Y is CN, n is 1 or 2.

L is hydrogen or nalinogen and each of M and Q is independently hydrogen, halogen, C1.C4 haloalkyl or C1.C4 haloalkoxy- Hal is Br or Cl and J is hydrogen or ethoxymethyl Halogeriation methods may be known methods such as decpptos in the Patents of the United States Nos. 5 010 098 and 5 449 789 Suitable akoxymethylamone processes for use in the present invention include conventional procedures known in the art (see, for example, U.S. Patent Nos. 5,010,098 and 5,359,090). In a preferred embodiment of the present invention, the alkoxymethylation process it consists in reacting a compound of formula VIII in which J is hydrogen with a compound d? - (alkoxyCi-Cejmetapo, N-N-dimethylformamide and phosphorus oxychloride in the presence of an aprotic solvent to form a reaction mixture and treat The reaction mixture with a tertiary amine In order to facilitate a better understanding of this invention the following examples are presented primarily for the purpose of illustrating the more specific details thereof. It should not be considered that the scope of the present invention is limited by these examples, but it covers the entire subject presented in the claims EXAMPLE 1 Preparation of N-. { 2,2,2-tr? FIuoroethyl) -4-chlorobenzamide using tetylamine as the base A mixture of 4-chlorobenzoyl chloride (64.6 g, 0.37 mol) and 2.2.2-tpfluoroethylamine hydrochloride (40.0 g, 0.37 mol) is treated at a rate such that the temperature is keep below 40 ° C. The reaction mixture is stirred overnight at room temperature and diluted with water and ethyl acetate. The organic layer is separated, washed with water and concentrated in vacuo to obtain a residue. The residue is crystallized from heptane to give the title product as a white solid (71.9 g, 81.7% yield, mp 108-111). ° C) latentificado by H-NMR and 1 &F ^ Using the same procedure, although using the appropriately substituted benzoyl chloride the following compounds are obtained: M Q? F ° C% yield H Br H 120 - 121 79, 1 H Cl Cl 128-135 91, 2 Cl H Cl 145 - 147 83.7 EXAMPLE 2 Preparation of N- (2,2,2-trifluoroethyl) -4-chlorobenzamide using sodium carbonate as the base A mixture of 2,2,2-trifluoroethiamine hydrochloride (100.0 g, 0.74 mol) and sodium carbonate (169.4 g, 1.6 mol) is treated in a 1: 1 mixture of toluene and water with 4-chloro chloride. -chlorobenzoyl (129.2 g, 0.74 mol) in a period of 30 minutes during which the temperature rises to 38 ° C, is stirred for one hour and diluted with ethyl acetate and water. The acucsa phase is separated and extracted with ethyl acetate. The organic phases are separated, washed with water, concentrated in vacuo and treated with heptane. The crystalline solids are filtered and dried to give the title product as a white solid. (175.8 g, 100% yield, mp 108, -1 12 ° C). Using the same procedure, although substituting 4-chlorobenzoyl chloride for 3,5-d-chlorobenzoyl chloride, N- (2,2,2-trifluoroethyl) -3,5-d-chlorobenzamide is obtained as a white solid, mp. 145-147 ° C, 95.5% yield EXAMPLE 3 Preparation of N- (2,2,2-trifluoroethyl) -4-chlorobenzimidoyl chloride using phosphorus pentachloride A mixture of N- (2,2,2-trifluoroethyl) -4-chlorobepzamide (65.0 g, 0.274 mol) and phosphorus pentachloride (57.0 g, 0.274 mol) is heated at 100 ° C and maintained at 100 ° C. that temperature for 2 hours. Once the phosphorus oxychloride is removed at a slightly lower vacuum, the title product is distilled in vacuo and collected in the form of a crystalline liquid (68.0 g, 96.9% yield, 'bp 91-92 °). C / 1.3 mm Hg). which is identified by 1 H and 19 F NMR Using essentially the same procedure, although using the duly substituted benzamide, the following compounds are obtained: Q • M Q pe / mmHg% yield H Br M 88 - 90 / 0.5 93.3 H Cl Cl 108 - 110 / 0.5 95.4 C! H Cl 101 - 103 / 0.5 90.7 EXAMPLE 4 Preparation of N- (2.2.2-tr? Fluoroetyl) -4-chlorobenzimido chloride using phosgene and N-N-dimethylformamide Treat a mixture of N- (2,2,2-trifluoroethylene) -4-chlorobenzamide (88.4 g, 0.37 mol) in a solution of phosgene in toluene (366.0 g as an aqueous solution). 20%, 0.74 mol) with N, N-dimethylformamide (54.0 g, 0.74 mol) over a period of 45 minutes during which the temperature rises to 50 ° C. The reaction mixture is then heated and maintained at 100 ° C for 4 hours. The toluene layer is separated and concentrated in vacuo to obtain a residue. The residue is distilled under vacuum to give the title product as a colorless oil (80, g, 84.5% yield, eg 81 ~ 83 ° C / 0. , 4 mHg). Using essentially the same procedure, but substituting N- (2,2,2-trifluoroethyl) -3,5-dichlorobenzamide for the N- (2,2,2-trifluoroetiyl) -4-chlorobepzamide, N- chloride is obtained. (2,2,2-trifluoroethyl) -3,5-dichlorobenzimidoyl as a colorless liquid, 62% yield EXAMPLE 5 Preparation of 2- (315-dichlorophenyl) -5- (trifluoromethyl) pyrrole-3-carbonitrile with 2 -cioroacr? lon? tplo Treat a solution of N- (2,2,2-trifluoroethyl) -3,5-dichlorobenzimidoyl chloride (8.72 g, 0.03 mol) in N, Nd? Methylformamide with 2.chloroacrylonitrile (3.0 g, 0.0345). mol) under a nitrogen atmosphere. Add tetylamine (0, 56 g, 0.0945 mo!) Slowly at 50 ° C over the course of three hours and the reaction mixture is stirred at 50 ° C for 17 hours. The mixture is then quenched with water and extracted with methylene chloride. The organic layer is washed with water and concentrated in vacuo to obtain a brown solid. Flash chromatography of the brown solid using silica gel and a 15% ethyl acetate solution in heptane gives the title product as a pale yellow solid (7.4 g, 80.9% yield). Following essentially the same procedure, although using the appropriately substituted benzimidoyl chloride and substituting triethylamine for * 1, 8-d? Azabicyclo [5, 4], undec-7-ene (DBU), the following compounds are obtained: M Q pf ° C% yield Cl H ^ Cl 87.4 H Br H 247.5 - 248.5 70.9 H '"Cl' Cl 87.4 H Cl H 39.4 EXAMPLE 6 Preparation of 2- (3,5-d? CJorophenol) -5- ( trifluoromethyl) pyrrole-3-carbonyl trile using 2,3-dichloropropionitrile Treat a solution of N- (2,2,2-trifluoroethyl) -3,5-dichlorobenzimidoyl chloride (8.72 g, 0.03 mol) in NN-dimethylformamide with 2,3-dichloropropionitrile (4.3 g) , 0.0345 mol) under nitrogen atmosphere. 1,8-Diazabicyclo [5.5.0] undec-7-ene (DBU) is added over the course of one hour at a rate such that the temperature of the reaction mixture is maintained at 50 ° C. Then the reaction mixture is maintained at 45 ° C for 2 hours and slowly quenched with aqueous HCl at 25 ° C. The brown solids are filtered, washed with water and dried in Jp vacuum oven at 60 ° C to give the title product as a brown solid * (8.64 g, 94.4% yield) which is identified. by 1 H and 19 F NMR. EXAMPLE 7 Preparation of methyl 2- (p-chlorophenyl) -5- (trifluoromethyl) pyrrole-3-carboxylate Treat a solution of N- (2,2,2-trifluoroethyl) -4-chlorobenzimidoyl chloride (10.2 g, 0.04 mol) and methyl 2-chloroacrylate (5.8 g, 0.048 mol) in NN-dimethylformamide with 1, 8-d? azab? c? clo [5 4.0] undec-7-ene (DBU) (19.5 g, 0.128 mol) over the course of thirty minutes at a rate such that the temperature of the reaction mixture is kept at 40 ° C, stirred for two hours and quenched with water and ethyl acetate. The organic layer is separated, washed sequentially with aqueous HCl and water and concentrated in vacuo to obtain an oil. Flash column chromatography of the oil using silica gel and a solution of 20% ethyl acetate in heptane and crystallization with heptane gives the title product as white crystals (4.2 g, 34.6% yield, mp 120.0 - 122.5 ° C). EXAMPLE 8 Preparation of 4-bromo-2- (3,5-dichlorophenyl) -5- (trifluoromethyl) pyrrol-3-carbonityl Br Treat a solution of N- (2.2.2-tr? Fluoroetii) -3,5-didorobenzimidoyl chloride (8.72 g, 0.03 mol) in NN-dimethylformamide with 2-chloroacplonitriio (3.0 g, 0.0345 mol) under an atmosphere of nitrogen. Tpetylamine (9.56 g, 0.9945 mol) is slowly added at 50 ° C over a period of two hours and the reaction mixture is stirred at 58 ° -60 ° C for 18 hours. Then bromine (4.8 g, 0.03 mol) is added in the course of 20 minutes as the temperature rises from 25 ° C to 36 ° C. The resulting reaction mixture is diluted with water and extracted with methylene chloride. Evaporation and flash column chromatography using silica gel and a 20% ethyl acetate solution in heptane gives the title product as a white crystalline solid (5.4 g, 46.9% yield) which is identified by NMR H and 19F.

It is noted that in relation to this date, the best method known to the applicant to carry out the said invention is that which is clear from the present description of the invention.

Claims

Ex iNDJCATiONS Having described the invention as above, the content of the following is claimed as property:

1. A process for the preparation of a 2-aryl-5- (perfluoroalkyl) pyrrol compound having the structural formula I (I) wherein W is hydrogen or CmF? m.i: Y is CN NO2 or CO2R. R is C1.C4 alkyl. ^ each of m and n is independently an integer of 1. 2, 3, 4, 5. 6, 7 u 8. L is hydrogen or halogen; each of M and Q is independently hydrogen, halogen, CN, NO

2. C 1 -C 4 alkyl: C 1 C 4 haloalkyl: C 1 -C 4 alkoxy: C 1 C 4 haloalkoxy. C1-C4 alkylthio; haloalkylthio C1.C4. C 1 -C 4 alkylsulfinyl; haloalkylsulfinyl C1.C4: alkylsuifonyl C. C; haloalkynesulfonyl C1.C4: o. when M and Q are in adjacent positions, they can be taken together with the carbon atoms to which they are joined to form a ring in which jV? Q represents the structure -OCH2O-. -OCF? O- or - CH = CH-CH = CH-; Ri. R2 and R3 are, independently, hydrogen, halogen. NO2, CHO or R2 and R3 can be taken together with the atoms to which they are attached to form a ring in which R2R3 is represented by the structure each of R *. R5 Re and R7 is independently hydrogen, halogen. CN or NO? and X is O c S the μ.u_? u this caa pai-zacb porch cmsistB in making re-encapment UQ cn-tpu? s clruco of N- (perfluoroalquilmetil) aril? m? doilo that has the structural formula II l (II) in which A and n are as described above, with a dienfilo compound having the structural formula II! or an a.β-dihalo compound having the structural formula IV z and 1 1 H. / HC- CH I I / w z (IV) (::: where W and Y are as described above and 2 is Cl. Br or I. and a base in the presence of a solvent 2. H. txuim of ipprh cm the reivirdirtrifV? 1, face more? -Bcb prryi »the base is present in an amount equal to at least 2 molar equivalents when the compound r / .p-dihalo having the structural formula IV is used.

3. O. 1111 -i-mi > and an '-t? 1 »rm the twj? rtt? i? - A-, (rlrl lM?? -_ l &{ lFfFi the 65 selected among the group that consists of a tri (al! Cj. In the case of a solvent, the solvent is selected from the group consisting of a carboxylic acid amide and a nitrophoid and mixtures thereof. the same 5 The agreement in accordance with the claim 1, in which the diepofüq is present in an amount of approximately one to four molar equivalents and the base is present in an amount of approximately one to four molar equivalents 6 The process according to claim 1, cara-acez-b because W is hydrogen, and CN is n or 1 or 2. L is hydrogen or halogen and each of M and Q is independently hydrogen, halogen, haloC1C4 haloalkoxy or haloalkoxy C? .C? 7 A process for the preparation of an arylpyrrole compound having the structural formula VIII u (VIII) in which Y is CN, NO2 or CO2R; R is C 1 -C 4 alkyl; p is an integer of 1, 2, 3, 4, 5, 6, 7 or 8; L is hydrogen or halogen, each of M and Q is independently hydrogen, halogen, CN, N02, C1.C4 alkyl, C1.C4 haloalkyl, C1.C4 alkoxy; haloalkoxy C1.C4, alkylthio C1.C4, haloalkyl. uncle C1.C

4. C 1 -C 4 alkylsulfamyl; haloalkylsulfinite C1.C4. ' alkylsulfonyl C ?. C. haloalkylsulfonyl C1.C4. or when M and Q are in adjacent positions, they can be taken together with the carbon atoms to which they are attached to form a ring in which MQ ^ represents the structure -OCH2O-, -OCF2O- or -CH = CH-CH = CH-. each of Ri. R2 and R3 is. independently, hydrogen, halogen, NO; CHO or R; and R3 can be taken together with the atoms to which they are attached to form a ring in which R2R3 is represented by the structure each of R4. R5 Re and Rr is independently hydrogen, halogen, CN or NO2, X is O or S, Hal is a halogen atom and J is hydrogen or alkoxymethyl Ci.Cß. the process is characterized in that it includes the following steps: a) reacting an N- (perfluoroalkylmethyl) arylimidoyl chloride compound of the formula II Cl A C n F 2 n + l (I I) wherein A and n are corr were described above with a dienophile compound having the structural formula IX or with an a.β-dihalo compound having the structural formula XI HC-CH? 3c = c: I I K z (IX) (XI) wherein Y is as described above and Z is Cl. Br or I, and a base in the presence of a solvent to form a 2-aryl-5- (perfluoroalkyl) pyrrol compound having the structural formula X b) halogenating the compound of the formula X to form the aplpyrrole compound of the formula VIII in which J is hydrogen and c) optionally, alkoxymethylating the compound of the formula VIII in which J is hydrogen 8 The process of acueedb with the reiviirticac 1 , csca &Erxz? cb P? TJP step (c) consists of reacting the compound of the formula VII; wherein J is hydrogen with a di (C? -C6 alkoxy) methane, N, Nd? methylformamide compound and phosphorus oxychloride in the presence of an aprotic solvent to form a reaction mixture and treat the reaction mixture with a tertiary amine. 9. A compound that has the structural formula II characterized because. n is an integer of 1. 2. 3, 4,

5.

6. 7 or 8; L is hydrogen or halogen; each of M and Q is independently hydrogen, halogen, CN, N02, C1.C4 alkyl. C1.C4 haloalkyl. C1.C4 alkoxy. haloalkoxy C1.C4. C 1 -C 4 alkylthio; Haloalkitiotium C1.C4. alkylsulfinyl C1.C4. haloalkylsulfamyl C1.C4; alkylsulfopyl d. C4 haloalkylsulfonyl C1.C4 or when M and Q are in adjacent positions, they can be taken together with the carbon atoms to which they are attached to form a ring in which MQ represents the structure -OCH O-, -OCF2O- or -CH = CH-CH = CH-, Ri. R and R3 are. independently, hydrogen, halogen, NO2, CHO or R2 and R3 can be taken together with the atoms to which they are attached to form a ring in which R2R3 is represented by the structure R Rc R, R, | «I 5! «I 7 each of R4. Rs. Re and R7 is independently hydrogen, halogen. CN or NO2 and X is O or S provided that when A is unsubstituted phenyl, p-orophenyl or p-methylphenyl, n 'is an integer that is not 1 10 The compound according to claim 9 characterized in that' n is 1 or 2; L is hydrogen or halogen and caaa one of M and Q and independently hydrogen, halogen, haloalkium C? .C? Or haloalkoxy C - .. C