Phenylselenyl bromide-induced cyclisation of γ- and δ-unsaturated aldoxime and ketoxime O-allyl and O-benzyl ethers is followed by a slow fragmentation furnishing cyclic imines which are readily reduced to pyrrolidines, piperidines or tetrahydroisoquinolines by sodium borohydride; dialkenyl oximes yield quinolizidines by an analogous sequence terminating in a mercury(II)-induced cyclisation.
苯基
硒溴化物诱导的γ-和δ-不饱和醛
肟和酮
肟O-烯丙基和O-苄基醚的环化反应,随后发生缓慢的断裂反应,生成环状
亚胺,后者很容易被
硼氢化钠还原为
吡咯烷、
哌啶或
四氢异喹啉;二烯基
肟通过类似的反应序列生成喹嗪,该反应以
汞(II)诱导的环化反应终止。