CS269080B1

CS269080B1 - Method of arenes' fluorinated derivatives preparation

Info

Publication number: CS269080B1
Application number: CS877184A
Authority: CS
Inventors: Josef Ing Csc Vencl; Vladimir Rndr Csc Chmatal; Zdenek Rndr Zuzanek; Zdenek Ing Vidner
Original assignee: Josef Ing Csc Vencl; Chmatal Vladimir; Zdenek Rndr Zuzanek; Zdenek Ing Vidner
Priority date: 1987-10-06
Filing date: 1987-10-06
Publication date: 1990-04-11
Also published as: CS718487A1

Abstract

Způsob přípravy fluorovaných derivátů arenů z chlor-, brom-, Si jodderivátů působením anorganických fluoridů v aprotickém prostředí při teplotě okolo 100 až 250 °C, s výhodou okolo 150 °C tak, že se do reakčního prostředí přidávají chemicky inertní, mechanicky odolné látky, popřípadě 0,01 až 10 % mol sloučenin fázových katalyzátorů a jako rozpouštědlo se s výhodou použije směsi rozpustidel s různou dielektrickou konstantou, přičemž soustava rozpouštědel může obsahovat 0,001 až 1 % hmot. vody. Připravené látky mají použití jako meziprodukty pro výrobu herbicidů, léčiv nebo barviv.Process for preparing fluorinated derivatives arenes from chloro-, bromo-, Si iodo derivatives by the action of inorganic fluorides in an aprotic environment at temperature about 100 to 250 ° C, preferably about 150 ° C by placing it in the reaction medium chemically inert, mechanically resistant substances, or 0.01 up to 10 mol% of the phase catalyst compounds and preferably as a solvent use mixtures of different solvents dielectric constant, with the system The solvent may contain 0.001 % to 1 wt. water. Prepared substances have use as intermediates for production herbicides, drugs or dyes.

Description

OS 269 080 B1 1

BACKGROUND OF THE INVENTION The present invention relates to a process for the preparation of fluorinated derivatives of arenes from aromatic chloro-, thio-derivatives by treatment with alkali fluoride by heating without a solvent or in aprotic anhydrous medium either without or in the presence of phase catalysts.

The classical method of introducing a fluorine atom into an aromatic nucleus is the Boltz-Schiemann reaction, which involves thermal decomposition of the fluoroborates of the aryldiazonium salt. A disadvantage of this process is the four-stage process consisting of nitration, reduction, diazotation and heat retardation. Another method is the transhalogenation of aromatic halogen derivatives with inorganic fluorides. The yields of this reaction range from 20 to 60% using a 2 to 3 molar excess of inorganic fluoride.

It has now been found that the heterogeneous reaction between the solid phase of inorganic fluorides and the solution of chlorinated or thickened derivatives of aromatic compounds can be accelerated, yields increased, and the amount of fluorides used in large excesses reduced. Slow reaction on the surface of the solid phase can be accelerated by restoring it by adding in the intermediate inert mechanically resistant particles which continuously disintegrate the surface of the inorganic phase and restore the surface of inorganic fluorides.

The principle of the preparation of fluorinated derivatives of arenes of general formula (IR)

where

R = C5, H02, FHX = P, H, 01, Br

T = P

chloro or bromo derivatives of the formula II wherein R = 05, 502, F, 3

A = 01, Br, HB = 01, Br, by treatment with inorganic fluorides in an aprotic environment at 100 ° C to 250 ° C, preferably 150 ° C, according to the invention. the compound or 0.01 to 10 mol% of the phase catalyst compounds and the solvent are a mixture of solvents with different dielectric constant, preferably dimethylformamide, benzonitrile, sulfonate, and other solvents with a relative permittivity of 30 to 60; . water. Among the inorganic fluorides, potassium fluoride, potassium hydrogen fluoride, fluoride ammonium, fluorides of other alkali metals and alkaline earth metals and fluorides of the divalent multivalent bonding elements with fluorine may be advantageously used. Solvents which may be used are preferably dimethylformamide, benzonitrile, sulfonate, and other solvents having a relative permittivity of 30 to 60%. water.

As the mechanically resistant particles, metal, preferably iron, porous and glass articles, preferably spherical or barrel-shaped, can be used.

Organic fluoro derivatives find increasing use in the dye chemistry, pesticide CS 269 080 B1 2 and pharmaceuticals, the following examples define, but not limit, the practice of the invention. Example 1

550 g of 2,6-dichlorobenzonitrile, 557 g of calcined fluoride, 550 ml of dimethylformamide and 30 iron balls of 0.6 cm in diameter are introduced into a 2 l autoclave. The autoclave is flushed with nitrogen and the reaction mixture is heated to 190 ° C for 16 hours. After, this time the reaction is over. The crude product is obtained by diluting 2 L of water and separating the organic phase. Of this, 355 g (80%) of 2,6-difluorobenzonitrile were obtained by distillation (90 ° C / 20 mm). Example 2

100 g of 2-chlorobenzonitrile, 63 g of calcined potassium fluoride, 100 ml of dimethyl foxamide and 20 iron balls of 0.6 cm in diameter are introduced into a 0.5 l autoclave. The autoclave is flushed with nitrogen and the reaction mixture is heated to 210 ° C and maintained at that temperature for 24 hours. Isolation of the product of Example 1. Distillation (92 ° C / 23 mm) gave 52.8 g (60%) of 2-fluorobenzonitrile. Example 3

100 g of 2,4-dichlorobenzobenzene, 90 g of annealed fluoride potassium, 2 g of 18-chloro-6, 100 ml of dimethyl foxamide and 20 iron balls of 0.6 cm in diameter are introduced into a 0.5 l autoclave. the reaction mixture was heated to 170 ° C and held at 14 hours. Isolation of the product of Example 1. Distillation (80-90 ° C / 10 mm) gave 55.9 g (72%) of 2,4-difluomitrobenzene. Example 4

100 g of 2,3-dichlorometrobenzene, 95 g of calcined fluoride, 3 g of tetrafenylphosphonium chloride, 100 ml of benzonitrile and 25 porcelain balls of 0.5 cm in diameter are introduced into a 0.5 l autoclave. The autoclave is flushed with nitrogen and heated to 210 ° C. After 15 hours of heating, the benzonitrile was distilled off and the product was isolated by vacuum reacting (75 to 82 ° / 10mm). Yield: 73.1 g of 3-chloro-2-fluoxnitrobenzene (80% of theory). Example 5

100 g of 1,3-dichlorofluorobenzene and 100 g of glass ballotine having a diameter of 4 mm are placed in a 0.5 l autoclave. The autoclave is purged with nitrogen and heated to 230 ° C for 24 hours. Vacuum rectification yields 63 g (70%) of 2,3-difluorochlorobenzene. Example 6

100 g of p-bromobenzonitrile, 50 g of calcined potassium fluoride, 5 g of fluoride, 100 ml of sulfolane, 2 g of tetramethylammonium chloride are introduced into a 0.5 l autoclave. 25 brass balls of 0.7 cm diameter are then added. After purging the autoclave with nitrogen, it was heated to 200 ° C for 6 hours. From the reaction mixture, the product was isolated by distillation under reduced pressure. 47.9 g of p-fluorobenzonitrile (72% of theory) are obtained.

Claims

EN 269 080 B1 SUBJECT MATTER OF THE PROCESS A process for preparing fluorinated arene derivatives of the general formula I H

Y / 1 / wherein R = CN, NOp, F, HX = F, H, Cl, Br Y = F 'from chloro or bromo derivatives of formula II RA / 11 / wherein R = CH, SO2, FHA = Cl , Br, HB = Cl, Br by treatment with inorganic fluorides in an aprotic environment at 100 ° C to 250 ° C, preferably 150 ° C, characterized in that chemically inert, mechanically resistant substances are added to the reaction medium. 0.01 to 10 mol% of the phase catalyst compounds and the solvent are used in a mixture of solvents with a different dielectric constant, preferably dimethylformamide, benzonitrile, sulfonate and other solvents with a relative permittivity of 30 to 60, and the solvent system may contain up to 1 wt. water.