JPS5830315B2 - Benzimidazolone Luino Seizouhouhou - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to a method for producing benzimidacylones.

More specifically, 0-dichlorobenzene or substituted 0-dichlorobenzene, an aqueous ammonia solution, and an alkali or alkaline earth metal carbonate or bicarbonate are reacted at high temperature and under pressure in the presence of a copper catalyst. This invention relates to a new method for directly producing benzimidasilones.

Traditionally, benzimidasilone was produced by reacting the hydrochloride of 0-phenylenediamine with excess phosgene in toluene, or by reacting 0-phenylenediamine and urea in an organic solvent.
It has been synthesized by a method of reaction at a temperature of 0 to 140°C.

The starting material for this known process, phenylenediamine, was conventionally obtained by synthesizing nitroaniline by ammonolysis of the corresponding chlornitrobenzene and subsequent reduction.

However, these methods have drawbacks such as high manufacturing costs due to long steps.

Benzimidacylones are useful as dye intermediates or resin raw materials, but the present inventors have investigated and developed a method for easily and inexpensively producing benzimidasilones by improving the above-mentioned drawbacks. The invented method has been completed.

In other words, in order to confirm the behavior of ammonolysis in the coexistence of alkali, we performed a pressurized reaction using 0-dichlorobenzene, an alkali or alkaline earth metal carbonate, and ammonia together, and found a surprisingly good yield. It was discovered that benzimidacylone can be obtained with

In order to confirm the benzimidabron produced by the method of the present invention, Chemical Abstracts, Vol. 25, 1503
As a result of mixing and comparing benzimidacylone synthesized by the method reported on this page and benzimidacylone obtained by the method of the present invention, R analysis and elemental analysis were performed, and it was confirmed that the two were exactly the same. did.

The O-dichlorobenzenes used as starting materials in the present invention include o-dichlorobenzene, which has CH3 in the benzene nucleus.
, lower alkyl-substituted O-dichlorobenzene with a lower alkyl group such as C2H5 group, or lower alkoxy-substituted O with a methoxy group, ethoxy group, etc. attached to the benzene nucleus
- Examples include dichlorobenzene.

The reaction temperature is preferably in the range of 170 to 2500C, particularly preferably in the range of 200 to 220C.

As the type of alkali used in combination with the ammonia aqueous solution, sodium carbonate is particularly preferred, but carbonates of alkaline earth metals such as calcium carbonate can also be used.

The copper compound to be used as a catalyst is generally one that can be used for ammonolysis of halogenated aromatic compounds. Combination use is preferred.

The filtrate obtained by filtering the benzimidacylone produced from the reaction solution has the following chemical formula: 2NH4C4+Na2CO3→2Na
As expressed by Cl+2NH3+H20+CO2,
It contains common salt produced by the decomposition of by-produced ammonia chloride, unreacted ammonia, a small amount of organic matter, and dissolved copper salt catalyst.

By absorbing ammonia into this filtrate again to achieve a predetermined ammonia concentration and reusing it for the next reaction, loss of ammonia and copper catalyst is prevented, reducing manufacturing costs and reducing waste liquid treatment costs. be able to.

Next, the present invention will be explained in more detail with reference to Examples.

Example 1 0-dichlorobenzene 54.5g, 28% ammonia water 450g, cuprous chloride 7.3g, copper powder 5.0g
and 74g of soda carbonate in a stainless steel 11
The mixture was charged into a volume autoclave and reacted at 210-215°C for 8 hours with stirring.

The pressure was 78-62 kl.

After the reaction was completed, the autoclave was cooled to room temperature, and the precipitated crystals were filtered out, washed with water, and dried to obtain 5 g of benzimidalone 3s (based on 0-dichlorobenzene, theoretical yield: 77%) having a melting point of 310 to 315°G.

Example 2 54.5 g of 0-dichlorobenzene, 450 g of 28% aqueous ammonia, 7.3 g of cuprous chloride, 5.0 g of copper powder, and 70 g of calcium carbonate were charged into an autoclave and reacted at 210'C for 8 hours.

After the reaction was completed, the reaction mixture was treated in the same manner as in Example 1 to obtain 35.5 g of benzimidasilon (based on o-dichlorobenzene, theoretical yield of 71%).

Example 3 3.4-dichlorotoluene 60g, 28% ammonia water 450g, cuprous oxide 5.3g, copper powder 5.0g
and 74g of soda carbonate into an autoclave 21
The reaction was carried out at 0°C for 8 hours, and after the completion of the reaction, the autoclave was cooled, the reaction product was taken out, and the precipitated crystals were treated in the same manner as in Example 1 to obtain 40g of 5-methylbenzimidacylon (3.5 g) having a melting point of 298-300°C. 4-dichlorotoluene (theoretical yield 75%) was obtained.

Claims (1)

[Claims] In the production of benzimidasilones represented by (wherein R represents a hydrogen atom, a lower alkyl group, or a lower alkoxy group), (wherein R is as defined above.) An 0-dichlorobenzene represented by A method for producing benzimidacilones, which comprises reacting with.