Selective One-Step Synthesis of Enantiopure <i>cis</i>-2,5-Disubstituted Pyrrolidines or <i>cis</i>-3,6-Disubstituted Piperidines from the (2<i>R</i>,2'<i>R</i>) (1,2-ethanediyl) Bis-aziridine
作者:Sébastien Fort、Isabelle McCort、Annie Duréault、Jean-Claude Depezay
DOI:10.1055/s-1997-1005
日期:1997.11
Nucleophilic ring opening of the optically active (1,2-ethanediyl) bis-aziridine 1 is dependent on the reagent and solvent. In aprotic medium cis-2,5-disubstituted pyrrolidines are formed from the opening of the aziridine ring at C-1 followed by intramolecular 5-exo-tet aminocyclization. With hydroxylated reagents in protic media, the opening takes place at C-2, leading to 3-hydroxy substituted piperidines via a 6-exo-tet cyclization process.
光学活性(1,2-乙烷二基)双氮丙啶 1 的亲核开环取决于试剂和溶剂。在壬烷介质中,氮丙啶环的 C-1 开环,然后发生分子内 5-外-四氨基环化反应,形成顺式-2,5-二取代吡咯烷。在质子介质中使用羟基化试剂时,C-2 开环,通过 6-外-四环化过程生成 3-羟基取代的哌啶类化合物。