Hydrochloric Acid → Benzene, (2,2-dichloro-1-methylcyclopropyl)-

Participants

Reaction Conditions

Reaction Steps

A solution of 3 g of triethylbenzylammonium chloride in 500 g of chloroform is added over the course of 5 minutes to 800 g of 50% strength by weight sodium hydroxide solution in a 2 l stirred apparatus equipped with a dropping funnel and internal thermometer, at 50° C., whilst cooling and stirring slowly. A solution of 345 g of α-methylstyrene in 300 g of chloroform is added dropwise over the course of 45 minutes to the preceding mixture with vigorous stirring and cooling at 50° C. After stirring for a further 4 hours at 50° C., the reaction mixture is cooled to 20° C. and neutralised with concentrated hydrochloric acid at 10°-20° C., whilst cooling. It is then diluted with 2 l of water and the organic phase is separated off. The aqueous phase is extracted with 100 g of chloroform. The combined organic phases are washed with 250 g of water and 100 g of 10% strength by weight sodium carbonate solution. The solvent is then distilled off and the residue is subjected to fractional distillation. This gives 561 g=92.9% of theory of 2,2-dichloro-1-methyl-1-phenyl-cyclopropane of boiling point 116°-117° C./17 mm.

Provenance & Evidence