title: Synthesis and characterization of bromonium ylides and their unusual ligand transfer reactions with N-heterocycles.
abstract: Stable aliphatic bromonium ylides (RfSO2)2C--Br+C6H4-p-CF3 (Rf = CF3, CF3(CF2)3) have been synthesized and structurally characterized for the first time. X-ray crystallographic analyses indicated a ylide structure with an sp2 hybridization of the ylide carbanions and with little double-bond character for the ylidic bond. The bromonium ylides selectively undergo transfer of the aryl group to nitrogen heterocycles, such as pyridines, yielding N-arylpyridinium salts. This is in a marked contrast to the reaction of the iodonium ylides, which produces pyridinium ylides through transylidations.
authors.affiliation: Faculty of Pharmaceutical Sciences, University of Tokushima, 1-78 Shomachi, Tokushima 770-8505, Japan.
authors.forename: Masahito
authors.initials: M
authors.lastname: Ochiai
authors.forename: Norihiro
authors.initials: N
authors.lastname: Tada
authors.forename: Kentaro
authors.initials: K
authors.lastname: Murai
authors.forename: Satoru
authors.initials: S
authors.lastname: Goto
authors.forename: Motoo
authors.initials: M
authors.lastname: Shiro