由酮和醛衍生的1-氯乙烯基对甲苯基亚砜与α-氰基碳负离子锂的加成反应以高收率或定量收率得到腈加合物。用过量的i- PrMgCl在THF中处理乙腈衍生的腈加合物,通过生成的镁类胡萝卜素的分子内S N 2烷基化反应生成氰基环丙烷。证明该反应的中间体是环丙基氯化镁,并且与亲电试剂反应,得到多取代的氰基环丙烷。在另一方面,腈加合物的反应从arylacetonitriles衍生与我-PrMgCl通过生成的镁类马鞭草中间体的1,3-碳-碳(1,3-CC)插入反应导致2-芳基氰基环丙烷的形成。发现该反应以高度立体定向的方式进行。关键反应,即镁类胡萝卜素的分子内S N 2烷基化和1,3-CC插入反应,是带有腈官能团的镁类胡萝卜素反应的第一个例子。
Towards nitrile-substituted cyclopropanes – a slow-release protocol for safe and scalable applications of diazo acetonitrile
作者:Katharina J. Hock、Robin Spitzner、Rene M. Koenigs
DOI:10.1039/c7gc00602k
日期:——
Diazo acetonitrile has long been neglected despite its high value in organicsynthesis due to a high risk of explosions. Herein, we report our efforts towards the transient and safe generation of this diazo compound, its applications in iron catalyzed cyclopropanation and cyclopropenation reactions and the gram-scale synthesis of cyclopropyl nitriles.