Cyclisation de N-tosyl oxiranes-propylamines: Synthese d'heterocycles azotes.
作者:A. Nuhrich、J. Moulines
DOI:10.1016/s0040-4020(01)96036-3
日期:1991.5
The cyclisation of N-tosyl-oxiranepropylamines is accomplished in aqueous basic medium and in anhydrous acid medium as well. In most cases, this reaction occurs by a regiospecific 5-exo-tet. ring closure and affords N-tosyl-2-pyrrolidinemethanols in high yields. The formation of N-tosyl-3-piperidinols through endo attack on the epoxide linkage is observed only in systems exhibiting geometric constraints
N-甲苯磺酰基-环氧乙烷丙胺的环化反应在水性碱性介质和无水酸介质中完成。在大多数情况下,该反应是通过区域特异性的5 -exo-tet发生的。闭环并以高收率提供N-甲苯磺酰基-2-吡咯烷甲醇。的形成Ñ甲苯磺酰基-3- piperidinols通过内上环氧化物配合攻击是在过渡态表现出几何约束系统只观察到。这些环化伴随着经历亲核攻击的碳的构型反转。因此,N-甲苯磺酰基-环氧乙烷丙胺的环化开辟了功能性吡咯烷的有效入口,并有望在合成中找到有用的应用。