Synthesis of New 5-Substituted Hydantoins from 2-Alkoxy- 1-cyano- 1-trimethylsiloxypropenes

摘要

Synthetic procedures for preparing previously unknown 5-(l'-alkoxyethylidene)hydantoins from 2-alkoxy-1-cyano-1-trimethylsiloxy-1-(or -2-)propenes by one-pot successive reactions with ethanol and (NH4)2CO3 are developed.Some intermediates,reaction mechanism,and parameters determining the optimal yields are considered.Acid hydrolysis of ethylidenehydantoins occurs at the vinyloxy group and gives 5-acetyl-hydantoin in 64% yield.