see text]. Intramolecular C-H insertion reaction of alpha-diazo-alpha-(phenylsulfonyl)acetamides proceeded with high regio- and stereoselectivities to afford highly functionalized gamma-lactams predominantly or exclusively. The high regioselectivity was attributed to the use of the phenylsulfonyl moiety, which altered electron density at the carbenoid center and exerted a steric effect during the insertion
[反应:请参见文字]。α-重
氮-α-(
苯磺酰基)乙
酰胺的分子内CH插入反应具有较高的区域选择性和立体选择性,从而主要或专门提供高度官能化的γ-内
酰胺。高区域选择性归因于
苯基磺酰基部分的使用,该部分改变了类
胡萝卜素中心的电子密度并在插入反应过程中产生了空间效应。本文还描述了确定区域选择性的三个控制元素,它们是
酰胺构象,立体电子和取代基效应。