Synthesis of Saturated Imidazolidin[1,5‐a]‐ and Thiazolidin[3,4‐a]perhydroquinoxalin‐4‐one and Imidazolidin[1,5‐a]piperazin‐4‐one Derivatives. Ring Contraction of Perhydroquinoxalin‐4‐one to Perhydrobenzimidazolin‐2‐one.

Abstract

In contrast to compound (I), piperazin-3-one (VIII) does not react with thiophosgene (II). Reaction of (I) with dibromoethane leads to an unusual contraction to give (VII). -(ZALESKA*, B.; SOCHA, R.; KARELUS, M.; GROCHOWSKI, J.; SERDA, P.; Synthesis 2004, 13, 2169-2172; Dep. Org. Chem., Jagiellonian Univ., PL-30-060 Krakow, Pol.; Eng.) -C. Herrmann