Cracked under strain: Strained allylic cyclobutanols and cyclopropanols readily undergo a ring expansion described by the title rearrangement. This reaction is promoted by catalytic amounts of 1 and displays high tolerance with respect to the substrate scope. The corresponding β‐fluoro spiroketone products are isolated in high yields and with excellent stereoselectivities. EDG=electron‐donating group
在应变下破裂:应变的烯丙基
环丁醇和
环丙醇很容易经历如标题重排所描述的环膨胀。该反应通过催化量为1来促进,并且相对于底物范围显示出高耐受性。相应的β-
氟螺酮产品以高收率和出色的立体选择性被分离出来。EDG =给电子基团,EWG =吸电子基团。