Abstract

A facile synthetic approach to 3-substituted-5-cyclopropanespirohydantoins has been developed and used to synthesize some new spirohydantoins. The key aspect is the preparation of α-carboethoxy isocyanate basing on Curtius rearrangement, which can be ring-closed to the expected spirohydantoins after the reaction with various amines and hydrazines. Interestingly the cyclopropane ring doesnt open during the whole process.

Keywords: Spirohydantions, N, N'-asymmetric ureas, cyclization, 1-(ethoxycarbonyl)-2, dimethylcyclopropanecarboxylic acid, Curtius rearrangement, α-carboethoxy isocyanate