JPS6023358A - 2,4,6-trifluorobenzonitrile - Google Patents

Abstract

NEW MATERIAL:2,4,6-Trifluorobenzonitrile. USE:An intermediate for agricultural chemicals, drugs, dye, etc. For example, an intermediate raw material for N-( 2,4,6-trifluorobenzoyl )-N'-[3, 5-dichloro-4-( 3- chloro-5-trifluoromethyl-2-pyridyloxy)phenyl]urea useful for controlling various kinds of insect pests. PREPARATION:2,4,6-Trichlorobenzonitrile is fluorinated to give 2,4,6-trifluorobenzonitrile. In the reaction, 2,4,6-trichlorobenzonitrile is reacted with potassium fluoride in an aprotic polar solvent such as dimethyl sulfoxide, etc. at 140-220 deg.C for 0.5-5hr.

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to a novel compound 2,4.6-)lifluorobenzonitrile. This product is useful as an intermediate raw material for various agricultural chemicals, medicines, dyes, etc.

2.4.6-) '7 Fluorobenzonitrile is produced by brominating '1.3゜5-trichlorobenzene to produce 2,4
．． It can be easily produced by preparing 6-) dichlorobromobenzene, then cyanating this to give 2.4, , 6-) dichlorobenzonitrile, and further fluorination.

2.4.Fluorination of 6-F-lichlorobenzonitrile
,4゜6-Trichlorobenzonitrile and potassium fluoride in an aprotic polar solvent such as dimethylsulfoxide, dimethylsulfone, sulfolane, 1.3-1-dimethyl-2-imigzolinonone, N-methyl-2-pyrrolidone, etc. 140-22
The reaction can be carried out at a temperature of 0° C. for 0.5=5 hours. Note that it is desirable to use dried and dehydrated potassium fluoride and the aprotic polar solvent.

2, 4 of the present invention. , 6-) Lifluorobenzonitrile can be chemically converted into compounds, dyes, and photographic materials that have this activity as agricultural chemicals and medicines, so these derivatives can be Useful as an intermediate for synthesis.

For example, 2.4,6-)lifluorobenzonitrile is added dropwise to 90% sulfuric acid and reacted at 70 to 80°C.
1.13-145℃) in methylene chloride,
(After adding oxalyl chloride dropwise at around 1'C, it is reacted under reflux to obtain 2.4.6-)lifluorobenzoyl isocyanate, and in a dioxane solution of this, 3,5-nochloro-4- (3-chloro-5
-) IJ fluoromethyl-2-bilinoloxy) aniline in dioxane solution is added dropwise to react, N-(2
,4, rottrifluorobenzoyl)-N'-(3,
5-dichloro-4-(3-2-chloro-5-trifluoromethyl-2-pyridyl)urea (melting point 226-229'C) or 2
＋'J is received.

This final compound, as described in Japanese Patent Application Laid-open No. 57-2258, is highly effective against the vJ of 4IIIJ harmful insects, especially the common insect pest.

Saiki 2, 4. , 6-) Lifluorobenz'amide' can be prepared by, for example, ``2, 4.6-1 LifluorobenzoniFlyl is vortexed in 70% IIIL acid and refluxed for 3 hours.
~・Let it react for 1 hour and then turn it off 2, 4.

6-1 Lifluorobenzoic acid (melting point l, to 41・1・12
．． 5° C.) by adding a halogenating agent, such as thionyl chloride: p, +1. , 6-) Lifluorobenzoic acid chloride and [7. Even if ammonia is applied to the second product, it will not bend.

Next, an example of the cooperative synthesis of the compound of the present invention will be described.

A (all 2.4. ('r-) Rifle A Robendzuni 1 s/l combination Ik 7 potassium chloride 3./l ε; g, dimethyl sulfoxide 2 (l r 2 c: and toluene 10
cc was put into the flask [5, the internal temperature was 2 (1 (1°C), and the water in the system was completely removed by azeotropic dehydration. Then, 2 g of 2,4.6-)lichlorobenzonitrile was added. -ζ The reaction was carried out under stirring and reflux for 3 hours. After the reaction was completed,
The product was poured into water and extracted with ether. The extracted layer was then dried and the 3-ether was distilled off to a boiling point of 106-108°C/75+
1.1 g of the target product of n+++ Hg was obtained.

In addition, 2, 4. used in the above synthesis example. ．． 6-) Lichlorobenzonitrile can be prepared by, for example, the following method (1).
．． 5-MJ Chlorobenzene is brominated to produce 2,4,6-)
Using dichlorobromobenzene, the second one is the Nobu method (2)
It can be obtained by cyanation with

(1) 2.4.6-) Synthesis of Lichlorobromobenzene 1.3.5-) 65 g of Lichlorobenzene was put into a flask, heated separately to 1'C to completely dissolve it, and then
After adding 4 g of aluminum chloride, 64 bromine was further added dropwise over about 6 hours to carry out a bromination reaction with stirring.

After the reaction was completed, the product was cooled and extracted by adding about 1 ρ of methylene chloride and 1 ρ of water. The extracted layer was washed with water and dried, then the methylene chloride was distilled off, and further rectified to give 2, 4., 6-
) Lichlorobromobenzene (melting point 63.4°C) 65.
I got 4B.

(2) Synthesis of 2.4.6-F-lichlorobenzonitrile Add 1.34 g of cupric cyanide to 3.4R of 2,4.6-)lichlorobromobenzene obtained by the method (1) above. Add 4 cc of trimethylformamide and raise the temperature to 155°.
The reaction was carried out with stirring at C for about 8:4 hours.

One hour after completion of the reaction, the product was poured into a 20% aqueous ferric chloride solution and extracted with methylene chloride. Next, methylene chloride in the extracted layer was distilled off, and the residue was filtered by column chromatography to obtain 1.55 g of 2.4.6-1-lichlorobenzonitrile having a melting point of 114-115'C.

Patent applicant: Ishihara Sangyo Co., Ltd. 15 complete

Claims (1)

[Claims] (1) 2,4.6-)lifluorobenzonitrile (2
) 2,4,6-) A method for producing 2,4,6-drifluorobenzonitrile, which comprises fluorinating dichlorobenzonitrile.