Potassium Hydroxide → methyl N-[4-(benzothiazol-2-ylmethoxy)-2-methylphenyl]carbamate

Participants

Reaction Steps

A solution of 3.6 g of potassium hydroxide in 10 ml of water was added to a solution of 10.0 g of methyl N-(4-hydroxy-2-methylphenyl)carbamate [prepared as described in Example 15(a) above] in 30 ml of dimethylformamide and 6 ml of water cooled in an ice-water bath. The resulting mixture was stirred at the same temperature for 20 minutes, and then a solution of 10.0 g of 2-chloromethylbenzothiazole in 25 ml of dimethylformamide was added to the reaction mixture. The temperature of the resulting mixture was elevated to room temperature and the mixture was stirred for 1 hour, at the end of which time the temperature was elevated further to 60° C. and the reaction mixture stirred for a further 2 hours. The reaction mixture was then poured into water to give a crystalline precipitate which was washed with water and further washed with diethyl ether and then recrystallised from ethyl acetate to give 10.5 g (yield 59%) of the title compound as a crystalline solid having a melting point of 147° to 149° C. The proton nuclear magnetic resonance spectrum was identical to that for the title compound of Example 21.

Provenance & Evidence