JPH085823B2 - Method for producing hexafluoroacetone or its hydrate - Google Patents

Method for producing hexafluoroacetone or its hydrate

Info

Publication number
JPH085823B2
JPH085823B2 JP63023753A JP2375388A JPH085823B2 JP H085823 B2 JPH085823 B2 JP H085823B2 JP 63023753 A JP63023753 A JP 63023753A JP 2375388 A JP2375388 A JP 2375388A JP H085823 B2 JPH085823 B2 JP H085823B2
Authority
JP
Japan
Prior art keywords
hydrate
hexafluoroacetone
ether
reaction
oxygen
Prior art date
Legal status (The legal status is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the status listed.)
Expired - Fee Related
Application number
JP63023753A
Other languages
Japanese (ja)
Other versions
JPH01203339A (en
Inventor
俊正 佐川
哲也 水野
竹比呂 園井
起正 山田
Current Assignee (The listed assignees may be inaccurate. Google has not performed a legal analysis and makes no representation or warranty as to the accuracy of the list.)
Nippon Mektron KK
Original Assignee
Nippon Mektron KK
Priority date (The priority date is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the date listed.)
Filing date
Publication date
Application filed by Nippon Mektron KK filed Critical Nippon Mektron KK
Priority to JP63023753A priority Critical patent/JPH085823B2/en
Priority to US07/189,034 priority patent/US4885398A/en
Priority to DE3816932A priority patent/DE3816932C2/en
Priority to US07/372,531 priority patent/US4960947A/en
Publication of JPH01203339A publication Critical patent/JPH01203339A/en
Publication of JPH085823B2 publication Critical patent/JPH085823B2/en
Anticipated expiration legal-status Critical
Expired - Fee Related legal-status Critical Current

Links

Classifications

    • YGENERAL TAGGING OF NEW TECHNOLOGICAL DEVELOPMENTS; GENERAL TAGGING OF CROSS-SECTIONAL TECHNOLOGIES SPANNING OVER SEVERAL SECTIONS OF THE IPC; TECHNICAL SUBJECTS COVERED BY FORMER USPC CROSS-REFERENCE ART COLLECTIONS [XRACs] AND DIGESTS
    • Y02TECHNOLOGIES OR APPLICATIONS FOR MITIGATION OR ADAPTATION AGAINST CLIMATE CHANGE
    • Y02PCLIMATE CHANGE MITIGATION TECHNOLOGIES IN THE PRODUCTION OR PROCESSING OF GOODS
    • Y02P20/00Technologies relating to chemical industry
    • Y02P20/50Improvements relating to the production of bulk chemicals
    • Y02P20/52Improvements relating to the production of bulk chemicals using catalysts, e.g. selective catalysts

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  • Catalysts (AREA)
  • Organic Low-Molecular-Weight Compounds And Preparation Thereof (AREA)
  • Low-Molecular Organic Synthesis Reactions Using Catalysts (AREA)

Description

【発明の詳細な説明】 〔産業上の利用分野〕 本発明は、ヘキサフルオロアセトンまたはその水和物
の製造法に関する。更に詳しくは、オクタフルオロイソ
ブテンの有効利用を兼ねたヘキサフルオロアセトンまた
はその水和物の製造法に関する。
TECHNICAL FIELD The present invention relates to a method for producing hexafluoroacetone or a hydrate thereof. More specifically, it relates to a method for producing hexafluoroacetone or a hydrate thereof that also serves to effectively utilize octafluoroisobutene.

〔従来の技術〕[Conventional technology]

ヘキサフルオロアセトンは、合成樹脂、合成ゴムなど
の製造用単量体として、あるいはビスフェノールAFなど
の架橋剤の中間体、医薬、農薬などの中間原料などとし
て用いられている。
Hexafluoroacetone is used as a monomer for producing synthetic resins and synthetic rubbers, as an intermediate for cross-linking agents such as bisphenol AF, and as an intermediate raw material for pharmaceuticals and agricultural chemicals.

このような各種の用途を有するヘキサフルオロアセト
ン水和物は、従来次のような方法によって製造すること
が提案されている。
Hexafluoroacetone hydrate having such various uses has been conventionally proposed to be produced by the following method.

しかしながら、上記の各方法には、次のような欠点が
みられる。
However, each of the above methods has the following drawbacks.

(1)過マンガン酸カリウムによる酸化反応は、反応が
激しくまた副生する二酸化マンガンが容易には処置でき
ない産業廃棄物となること (2)ヘキサフルオロプロペンより合成されるそのオキ
サイドは高純度のものが得られ難く、従って生成物たる
ヘキサフルオロアセトン中にヘキサフルオロプロペンな
どが混在すること (3)ジエチタン(ヘキサフルオロチオアセトン2量
体)の硝酸酸化では、得られるヘキサフルオロアセトン
水和物中に、NO2およびSO2が含まれ、それの除去に手間
がかかること (4)ヘキサクロルアセトンの使用は、合成上塩素が重
量を増加させるだけで効率的ではなく、また有毒な五塩
化アンチモンを必要とし、更に高純度の生成物が得られ
難いこと 〔発明が解決しようとする課題〕 本発明は、かかる欠点がみられるこれらの従来技術と
は全く発想を異にし、それの有効利用が強く求められて
いるオクタフルオロイソブテンを出発物質として用い、
ヘキサフルオロアセトンまたはその水和物を製造するこ
とを目的とする。
(1) The oxidation reaction by potassium permanganate is vigorous, and the by-product manganese dioxide becomes industrial waste that cannot be easily treated. (2) The oxide synthesized from hexafluoropropene has a high purity. Therefore, hexafluoropropene and the like are mixed in the product hexafluoroacetone. (3) In the nitric acid oxidation of dietitanium (hexafluorothioacetone dimer), hexafluoroacetone hydrate is obtained. , NO 2 and SO 2 are contained, and it takes time to remove them. (4) The use of hexachloroacetone is not efficient because only chlorine increases the weight in synthesis, and toxic antimony pentachloride is not used. It is necessary, and it is difficult to obtain a product of higher purity. [Problems to be Solved by the Invention] The idea is completely different from these conventional techniques, and octafluoroisobutene, which is strongly demanded to be effectively used, is used as a starting material.
The purpose is to produce hexafluoroacetone or its hydrate.

〔課題を解決するための手段〕[Means for solving the problem]

かかる本発明の目的は、オクタフルオロイソブチルア
ルキル、アリールまたはベンジルエーテルあるいはヘプ
タフルオロイソブテニルアルキル、アリールまたはベン
ジルエーテルを酸素および活性炭触媒の存在下に約50〜
600℃の温度で熱分解させ、ヘキサフルオロアセトンま
はたその水和物を取得することにより達成される。
Such an object of the invention is to add octafluoroisobutylalkyl, aryl or benzyl ether or heptafluoroisobutenylalkyl, aryl or benzyl ether in the presence of oxygen and activated carbon catalyst to about 50-
It is achieved by pyrolyzing at a temperature of 600 ° C. and obtaining hexafluoroacetone or its hydrate.

そもそもの出発物質として用いられるオクタフルオロ
イソブテンは、含フッ素共重合体の重要な原料の一種で
あるヘキサフルオロプロペン製造時の副生成物であり、
この毒性の強いオクタフルオロイソブテンは、一般に低
級アルコール、例えばメタノール、エタノール、n−プ
ロパノール、イソプロパノール、n−ブタノールなどと
のアルコール付加物たるオクタフルオロイソブチルアル
キルエーテルを容易に形成する性質を有している。同様
に、フェノール類またはベンジルアルコールとの付加物
からは、アリールエーテルまたはベンジルエーテルが形
成される。
Octafluoroisobutene used as the starting material in the first place is a by-product during the production of hexafluoropropene, which is one of the important raw materials for the fluorine-containing copolymer,
This highly toxic octafluoroisobutene generally has a property of easily forming octafluoroisobutyl alkyl ether which is an alcohol adduct with a lower alcohol such as methanol, ethanol, n-propanol, isopropanol, n-butanol and the like. . Similarly, aryl ethers or benzyl ethers are formed from adducts with phenols or benzyl alcohol.

これらのオクタフルオロイソブチルエーテルは、第4
級アンモニウム塩などの相間移動触媒の存在下に、アル
カリ金属またはアルカリ土類金属の水酸化物または炭酸
塩あるいはトリアルキルアミンなどの塩基と共に攪拌す
ることにより脱フッ化水素化され、対応するヘプタフル
オロイソブテニルアルキル、アリールまたはベンジルエ
ーテルを与える。
These octafluoroisobutyl ethers are
It is dehydrofluorinated by stirring with a hydroxide or carbonate of an alkali metal or alkaline earth metal or a base such as a trialkylamine in the presence of a phase transfer catalyst such as a primary ammonium salt, and the corresponding heptafluoro This gives isobutenyl alkyl, aryl or benzyl ethers.

本発明方法においては、オクタフルオロイソブチルエ
ーテルおよびそれから導かれるヘプタフルオロイソブテ
ニルエーテルのいずれをも原料物質として用いることが
できる。これに対して、先に本出願人によって提案され
た方法、即ち、ヘプタフルオロイソブテニルエーテルを
光照射下に酸素と反応させ、ヘキサフルオロアセトンま
たはその水和物を製造する方法(特開昭61−277,645号
公報)では、ヘプタフルオロイソブテニルエーテルのみ
が原料物質となり得て、オクタフルオロイソブテニルエ
ーテルは原料物質として使用することができない。
In the method of the present invention, both octafluoroisobutyl ether and heptafluoroisobutenyl ether derived therefrom can be used as the starting material. On the other hand, the method previously proposed by the applicant of the present invention, that is, a method for producing hexafluoroacetone or a hydrate thereof by reacting heptafluoroisobutenyl ether with oxygen under light irradiation (Japanese Patent Application Laid-Open No. S60-12065) 61-277,645), only heptafluoroisobutenyl ether can be a starting material, and octafluoroisobutenyl ether cannot be used as a starting material.

これらの各原料物質を用いての熱分解反応は、常圧下
または加圧下に、活性炭触媒を充填した金属製反応管
に、酸素または酸素含有ガスに同伴させた原料物質(酸
素/原料物質モル比約1〜2)を供給し、反応管を通過
させる間に熱分解させることにより行われる。
The thermal decomposition reaction using each of these raw materials is carried out under normal pressure or under pressure, in a metal reaction tube filled with an activated carbon catalyst, the raw material (oxygen / raw material molar ratio of oxygen / oxygen-containing gas). It is carried out by supplying about 1-2) and pyrolyzing it while passing it through the reaction tube.

触媒として用いられる活性炭は、粉末状、顆粒状、粉
状、ハニカム状、棒状、筒状など任意の形状のものを用
いることができ、特に内部比表面積が約10〜3000m2/g、
好ましくは約200〜2000m2/gの顆粒状物を用いることが
望ましい。
The activated carbon used as a catalyst can be used in any shape such as powder, granules, powder, honeycomb, rod, and cylinder, and particularly has an internal specific surface area of about 10 to 3000 m 2 / g,
It is desirable to use about 200 to 2000 m 2 / g of granular material.

このような活性炭触媒を用いての反応は、約50〜600
℃、好ましくは約150〜300℃の温度で行われる。これよ
り低い温度では、熱分解速度が遅くなりすぎて経済上お
よび効率上の観点から好ましくなく、一方これより高い
温度では、エネルギーコストおよび反応器材質の劣化が
加速されるので好ましくない。
The reaction using such an activated carbon catalyst is about 50 to 600.
C., preferably at a temperature of about 150-300.degree. A temperature lower than this is not preferable from the economical and efficiency viewpoint because the thermal decomposition rate becomes too slow, while a temperature higher than this is not preferable because the energy cost and deterioration of the reactor material are accelerated.

反応終了後は、反応混合物を順次水トラップおよびド
ライアイス−メタノールトラップへと導き、生成物を捕
集する方法が一般にとられる。水トラップには、ヘキサ
フルオロアセトンが水和物として得られる。得られたヘ
キサフルオロアセトンの水和物は、それ自体ポリエステ
ル、ポリアミドなどの溶媒として使用できるが、それの
脱水を行う場合には、五酸化リン、濃硫酸、無水硫酸あ
るいはモレキュラシーブなどを用いる方法によって行う
ことができる(特開昭57−81,433号公報、同59−157,04
5号公報)。
After completion of the reaction, generally, the reaction mixture is introduced into a water trap and a dry ice-methanol trap to collect the product. Hexafluoroacetone is obtained as a hydrate in the water trap. The obtained hexafluoroacetone hydrate itself can be used as a solvent for polyester, polyamide, etc., but when dehydrating it, phosphorus pentoxide, concentrated sulfuric acid, sulfuric anhydride, molecular sieves or the like is used. Can be carried out (JP-A-57-81,433, JP-A-59-157,04).
No. 5 bulletin).

この熱分解反応で得られる分解ガス中のヘキサフルオ
ロアセトンは、GLC分析法によりその生成を確認するこ
とができるが、その分解ガス組成中には他の副生ガスが
含まれているため、ヘキサフルオロアセトンをそのまま
分離せず、一旦水中に分解ガスを導いて水和物とし、そ
れを分離する方法が簡単かつ便利な方法として用いられ
るのである。
Hexafluoroacetone in the decomposition gas obtained by this thermal decomposition reaction can be confirmed by GLC analysis for its formation, but since the decomposition gas composition contains other by-product gases, A method in which fluoroacetone is not separated as it is, but a decomposition gas is once introduced into water to form a hydrate and the hydrate is separated is used as a simple and convenient method.

〔発明の効果〕〔The invention's effect〕

本発明方法に従がい、ヘキサフルオロアセトンまたは
その水和物がオクタフルオロイソブチルエーテルまたは
ヘプタフルオロイソブテニルエーテルの熱分解という全
く新規な反応方法により得られた。この方法は、オクタ
フルオロイソブテンの有効利用法としても有意義であ
る。
According to the method of the present invention, hexafluoroacetone or a hydrate thereof was obtained by a completely novel reaction method of thermal decomposition of octafluoroisobutyl ether or heptafluoroisobutenyl ether. This method is also significant as an effective method for utilizing octafluoroisobutene.

〔実施例〕〔Example〕

次に、実施例について本発明を説明する。 Next, the present invention will be described with reference to examples.

実施例1 焼成した活性炭110gを充填したステンレス鋼製反応管
を200℃の温度に加熱し、反応管上方よりオクタフルオ
ロイソブチルメチルエーテル150g(純度70%、0.45モ
ル)を酸素ガス11(0.49モル)に同伴させながら、1.
6時間の間に仕込んだ。この際、反応管中を通過したガ
スは容量300mlの容器中の水100ml中に導き、更に容量50
0mlのドライアイス−メタノールトラップを経て放出し
た。
Example 1 A stainless steel reaction tube filled with 110 g of fired activated carbon was heated to a temperature of 200 ° C., and 150 g of octafluoroisobutyl methyl ether (purity 70%, 0.45 mol) was added to the oxygen gas 11 (0.49 mol) from above the reaction tube. While accompanied by 1.
It was prepared in 6 hours. At this time, the gas passing through the reaction tube was introduced into 100 ml of water in a container of 300 ml in volume, and the volume of 50 ml was further increased.
It was discharged via a 0 ml dry ice-methanol trap.

その時点で、水トラップ(内容量129.2g)中には約1
8.9重量%の濃度でヘキサフルオロアセトン水和物(HF
A.H2O)が生成していることがF−NMR内標法により確認
され、またドライアイス−メタノールトラップ中にも約
18重量%の濃度でヘキサフルオロアセトン水和物を含む
水層2.95gのあることが同様に確認され、これらの水層
以外に45.7gの原料が回収された。なお、水層からのヘ
キサフルオロアセトン水和物の分離は、エーテル系溶媒
を用いる抽出法により容易に行なうことができる。
At that point, about 1 in the water trap (129.2g content)
Hexafluoroacetone hydrate (HF at a concentration of 8.9% by weight)
AH 2 O) was confirmed to be produced by the F-NMR internal standard method, and it was also observed in a dry ice-methanol trap.
It was similarly confirmed that there were 2.95 g of an aqueous layer containing hexafluoroacetone hydrate at a concentration of 18% by weight, and 45.7 g of raw material was recovered in addition to these aqueous layers. The hexafluoroacetone hydrate can be easily separated from the aqueous layer by an extraction method using an ether solvent.

実施例2 実施例1の熱分解反応において、オクタフルオロイソ
ブチルメチルエーテルの代りにヘプタフルオロイソブテ
ニルメチルエーテル150g(純度87%、0.61モル)を用
い、酸素ガス16.4l(0.73モル)に同伴させながら、2
時間の間に仕込んだ。
Example 2 In the thermal decomposition reaction of Example 1, 150 g of heptafluoroisobutenyl methyl ether (purity 87%, 0.61 mol) was used in place of octafluoroisobutyl methyl ether, and the mixture was made to accompany 16.4 l (0.73 mol) of oxygen gas. While 2
Prepared during the time.

反応終了後の水トラップ(内容量121.1g)中には約2
2.9重量%の濃度でヘキサフルオロアセトン水和物が生
成しており、またドライアイス−メタノールトラップ中
にも約23重量%の濃度でヘキサフルオロアセトン水和物
を含む水層19.6gが存在しており、これらの水層以外に1
4.3gの原料が回収された。
Approximately 2 in the water trap (content 121.1g) after the reaction
Hexafluoroacetone hydrate was produced at a concentration of 2.9% by weight, and 19.6 g of an aqueous layer containing hexafluoroacetone hydrate at a concentration of about 23% by weight was also present in the dry ice-methanol trap. And in addition to these water layers 1
4.3 g of raw material was recovered.

実施例3 実施例1の熱分解反応において、オクタフルオロイソ
ブチルメチルエーテルの代りにヘプタフルオロイソブテ
ニルベンジルエーテル150g(純度85%、0.44モル)を用
い、酸素ガス11.9l(0.53モル)に同伴させながら、1.7
時間の間に仕込んだ。
Example 3 In the thermal decomposition reaction of Example 1, 150 g of heptafluoroisobutenyl benzyl ether (purity 85%, 0.44 mol) was used in place of octafluoroisobutyl methyl ether, and 11.9 l (0.53 mol) of oxygen gas was allowed to accompany it. While 1.7
Prepared during the time.

反応終了後の水トラップ(内容量128.0g)中には約1
8.5重量%の濃度でヘキサフルオロアセトン水和物が生
成しており、またドライアイス−メタノールトラップ中
にも約19重量%の濃度でヘキサフルオロアセトン水和物
を含む水層2.1gが存在しており、これらの水層以外に5
8.6gの原料が回収された。
Approximately 1 in the water trap (content 128.0g) after the reaction
Hexafluoroacetone hydrate was produced at a concentration of 8.5% by weight, and 2.1 g of an aqueous layer containing hexafluoroacetone hydrate at a concentration of about 19% by weight was also present in the dry ice-methanol trap. There are 5 other than these water layers.
8.6g of raw material was recovered.

───────────────────────────────────────────────────── フロントページの続き (51)Int.Cl.6 識別記号 庁内整理番号 FI 技術表示箇所 C07B 61/00 300 ─────────────────────────────────────────────────── ─── Continuation of the front page (51) Int.Cl. 6 Identification code Internal reference number FI technical display location C07B 61/00 300

Claims (2)

【特許請求の範囲】[Claims] 【請求項1】オクタフルオロイソブチルアルキル、アリ
ールまたはベンジルエーテルを酸素および活性炭触媒の
存在下に約50〜600℃の温度で熱分解させることを特徴
とするヘキサフルオロアセトンまたはその水和物の製造
法。
1. A process for producing hexafluoroacetone or a hydrate thereof, which comprises thermally decomposing octafluoroisobutylalkyl, aryl or benzyl ether at a temperature of about 50 to 600 ° C. in the presence of oxygen and an activated carbon catalyst. .
【請求項2】ヘプタフルオロイソブテニルアルキル、ア
リールまたはベンジルエーテルを酸素および活性炭触媒
の存在下に約50〜600℃の温度で熱分解させることを特
徴とするヘキサフルオロアセトンまたはその水和物の製
造法。
2. Hexafluoroacetone or its hydrate characterized in that heptafluoroisobutenylalkyl, aryl or benzyl ether is pyrolyzed at a temperature of about 50 to 600 ° C. in the presence of oxygen and an activated carbon catalyst. Manufacturing method.
JP63023753A 1987-07-21 1988-02-05 Method for producing hexafluoroacetone or its hydrate Expired - Fee Related JPH085823B2 (en)

Priority Applications (4)

Application Number Priority Date Filing Date Title
JP63023753A JPH085823B2 (en) 1988-02-05 1988-02-05 Method for producing hexafluoroacetone or its hydrate
US07/189,034 US4885398A (en) 1987-07-21 1988-05-02 Process for producing hexafluoroacetone or its hydrate
DE3816932A DE3816932C2 (en) 1987-07-21 1988-05-18 Process for the preparation of hexafluoroacetone and its hydrate
US07/372,531 US4960947A (en) 1987-07-21 1989-06-28 Process for producing hexafluoroacetone or its hydrate

Applications Claiming Priority (1)

Application Number Priority Date Filing Date Title
JP63023753A JPH085823B2 (en) 1988-02-05 1988-02-05 Method for producing hexafluoroacetone or its hydrate

Publications (2)

Publication Number Publication Date
JPH01203339A JPH01203339A (en) 1989-08-16
JPH085823B2 true JPH085823B2 (en) 1996-01-24

Family

ID=12119079

Family Applications (1)

Application Number Title Priority Date Filing Date
JP63023753A Expired - Fee Related JPH085823B2 (en) 1987-07-21 1988-02-05 Method for producing hexafluoroacetone or its hydrate

Country Status (1)

Country Link
JP (1) JPH085823B2 (en)

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JP4534274B2 (en) * 1999-09-13 2010-09-01 ユニマテック株式会社 Method for producing hexafluoroacetone or hydrate thereof
JP4396831B2 (en) 2004-04-19 2010-01-13 ダイキン工業株式会社 Method for producing fluoroalkyl ketone hydrate
JP5315609B2 (en) 2006-06-05 2013-10-16 ダイキン工業株式会社 Novel carboxylic acid compound, its use and production method
JP5114880B2 (en) 2006-07-06 2013-01-09 ダイキン工業株式会社 Novel α-fluoromethoxycarboxylic acid ester, method for producing the α-fluoromethoxycarboxylic acid ester, and method for producing sevoflurane
JP5163064B2 (en) 2007-11-13 2013-03-13 ダイキン工業株式会社 Novel carboxylic acid ester, its use and production method
JP5482013B2 (en) * 2009-08-18 2014-04-23 セントラル硝子株式会社 Method for producing hexafluoroacetone monohydrate
JP5585291B2 (en) * 2010-08-12 2014-09-10 セントラル硝子株式会社 Method for producing hexafluoroacetone monohydrate

Also Published As

Publication number Publication date
JPH01203339A (en) 1989-08-16

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