SU1512966A1 - Method of producing 4-(methylamino)-biphenyl - Google Patents

Abstract

The invention relates to aromatic amines, in particular to the preparation of a 4- (methyamino) -biphenyl intermediate in the synthesis of dyes, insecticides, antioxidants. The goal is to simplify the process. Obtaining the desired product is carried out by reacting biphenyl with N-methylhydroxylamine in the presence of iron lactate (2+), taken in an amount of 0.17-1.00 mol per 1 mol of biphenyl, and methanesulfonic acid, taken in an amount of 1.78-3, 50 mol per 1 kg of the reaction mass, in the medium of nitrobenzene or nitromethane, taken in an amount of 0.4-1.2 l per 1 mol of biphenyl, at 100-130 ° C. These conditions eliminate the need to work under pressure when using available biphenyl. 1 hp f-ly, 1 tab.

Description

The invention relates to an improved process for the preparation of 4- (methylamino) biphenyl, used as an intermediate in the synthesis of dyes, insecticides, antioxidants.

The aim of the invention is to simplify the process and increase its efficiency.

EXAMPLE 1. In a single-neck flask equipped with a condenser, a shutter and a root stirrer and placed in an oil bath, 10 g- (0.065 mol) of biphenyl, 1.8 g (0.021 col) N-methyl-hydroxylamine hydrochloride are charged. (MHA - HC1), 3.1 g (0.011 mol) of ferrous lactate, 20.8 g (0.22 mol) of methanesulfonic acid, and 26 tin of nitromethane. The flask is maintained in an oil bath for 5 hours with efficient stirring. After the end of the process, the mixture is cooled, neutralized with ammonia, the solvent is distilled off (nit- .- rbmethane), the bottom residue is filtered off, washed on the filter with hot carbon chloride or chloroform. After complete evaporation of the aqueous solution and treatment with an equivalent amount of sulfuric acid, methanol sulfonic acid is recovered by vacuum distillation, which can be used for subsequent experiments.

The organic layer is extracted with hot dilute hydrochloric acid (1:10) to isolate the desired pro-; duct. The residue after extraction is used to isolate unreacted biphenyl. The acidic aqueous extract is neutralized with ammonia, the desired product is isolated by extraction with four chlorine chlorine with carbon or chloroform.

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2.3 g of 4- (methylamiio) biphenyl (yield 59%) based on N-methylhydroxylamine are obtained. The desired product is individual according to GLC.

Terms of PKH-analysis: Chrome chromatograph 5 (Czechoslovakia) with an integrator, a column of 1-1.25 m glass, filled with Super inert with 3% SP-2100. Carrier gas helium, analysis temperature 160 °, DIP.

The target product was characterized by a T.p. of its N-benzene sulphamide derivative 152-153 s (t.pl. lit. 152-.

Crimer2, 3.4 g (0.022 mol) of biphenyl, 1.812 g (0.022 mol) of N-methylhydroxylamine hydrochloride, 3.4 g (0.012 mol) of ferrous iron lactate, 23 g (0.24 mol) of methanesul are loaded into the reaction flask. - phacid and 30 ml of nitrobenzene. The process temperature, time 6 hours. After the end of the process, the mixture is cooled, neutralized with ammonia, the solvent (nitrobenzene) is distilled off with water vapor. Subsequently, the treatment of the reaction mixture is carried out as described in Example 1. 0.85 g of the expected product is obtained. (yield 17%)

Example 3 (comparative) The process is carried out as described in Example 1, but using p-toluenesulfonic acid as the acid component and nitrobenzene as the solvent. The yield of the target product is 8.5%.

Examples 4-17. The process is carried out under the conditions of examples 1 or 2, respectively.

The values of the parameters and the results of the process are presented in the table,

Claims (1)

The technical and economic efficiency of the proposed method is to simplify the process, since it eliminates the work under pressure, and also improves the efficiency of the process j, since much more affordable raw materials are used - biphenyl (instead of 4-chlorobiphenyl), the Invention Formula 1, a method for producing 4- (methylamino) biphenyl by reacting a diphenyl derivative with a methyl amine in the presence of a catalyst in an inert solvent at elevated temperature, characterized in that, in order to simplify the process and increase its efficiency, biphenyl is used as a diphenyl derivative, as the amine, H-methylhydroxy-amine, as a catalyst, lacquer, tat of iron (II), taken in an amount of 0.17-1.00 mol per 1 mol of biphenyl, and methanesulfonic acid, taken in an amount of 1, 78-3.50 mol per 1 kg of the reaction mass, as a solvent. Nitrobenzene or nitromethane is used and the process is carried out at 100-130 ° C, 2, the method according to claim 1, differing from that by the fact that nitrobenzene or nitromethane is used in an amount of 0.4-1 e2 l per 1 mole of biphenyl. Table continuation  Calculation for N-methylhyproxylamine. The composition of the target product is marked by the admixture of a significant amount of isomeric aminobiphenyls (A-YuH). 3-pitch tar, Product - high quality as amines.