Urea → N-(4,5,6,7-Tetrahydro-1-benzothiophen-4-yl)urea

Participants

Reaction Conditions

Reaction Steps

A 1 gram sample of 4-hydroxy-4,5,6,7-tetrahydrobenzo[b]thiophene is stirred in the cold for several hours in thionyl chloride (5 ml.) and the mixture is evaporated to dryness. The crude 4-chloro-4,5,6,7-tetrahydrobenzo[b]thiophene is then added to a mixture of urea (1- 5 mole-equivalents) in dimethylformamide and diisopropyl ethylamine. The mixture is warmed, after several hours, to 50° C. and after 4 hours is poured on ice and the product, 4,5,6,7-tetrahydrobenzo[b]thien-4-ylurea, is collected by filtration.

Provenance & Evidence