THE SYNTHESIS OF BICYCLIC PHOSPHONIUM SALTS

Abstract

Bicyclic phosphonium salts (1–6), (9) and (15) have been prepared by three routes, i.e. the Diels Alder cycloaddition reactions of vinyltriphenylphosphonium bromide with cyclopentadiene and anthracene and its derivatives; the alkylation of tertiary phosphines by 2- and 7-bromotrinorbornanes; and via the free-radical addition of diphenylphosphine to trinorbornene followed by the alkylation of the resultant 2-trinorbornyldiphenylphosphine using iodomethane and iodoethane. Chromatographic methods were developed for the purification of the salts which were characterised by ¹H, ¹³C and ³¹P n.m.r. spectroscopy.