Neighboring effect of pyrazole rings: regio- and stereoselective Wagner-Meerwein rearrangement in electrophilic addition reactions of norbornadiene-fused pyrazoles

摘要

The electrophilic addition reactions of norbornadiene-fused pyrazoles with bromine or p-nitrobenzenesulfenyl chloride provided the skeletally rearranged adducts regio- and stereoselectively probably via the neighboring group participation of a pyrazole ring accompanied by the formation of a bridged pyrazolium ion. [References: 25]