The sulphone group as a nucleophile: intramolecular formation of a novel thiadecanylium tribromide via addition of bromine to a double bond in an overcrowded environment

Abstract

Instead of furnishing a normal bromide addition product, bromination of 4-thiatricyclo[5.2.0.0^2,6]non-8-ene 4-4-dioxide (1) gives 5-bromo-1-oxo-10-oxa-1λ⁶-thiatetracyclo[4.3.1.0^3,8.0^4,7]decan-1-ylium tribromide (3) through intramolecular reaction of the bromonium intermediate with the adjacent weakly nucleophilic sulphone group.