Stereochemical evidence for stabilization of a nitrogen cation by neighboring chlorine or bromine

ABSTRACT: Neighboring group participation is one of the fundamental interactions in organic reactions and can influence the reaction rate, stereoselectivity, and reaction pathway through transient carbon-carbon or carbon-heteroatom bond formation. The latter category includes cyclic three- and five-membered bromonium ions, wherein lone-pair electrons of the monovalent bromine atom stabilize a trigonal carbocation. Although similar nucleophilic interactions of monovalent halogen atoms with non–carbon atom-centered cations have long been predicted, we know of no experimental evidence of such an interaction. Here, we demonstrate a nucleophilic interaction of neighboring monovalent halogen to stabilize an imino sp2 nitrogen cation. This interaction has an overwhelming impact on the reaction pathway, com

SUBMITTER: Ohwada T 

PROVIDER: S-EPMC3600509 | biostudies-literature | 2013 Feb

REPOSITORIES: biostudies-literature