Benzyltriphenylphosphonium bromide is used as a reactant for stereoselective azidolysis of vinyl epoxides, enantioselective aziridination and Friedel-Crafts cyclization for asymmetric synthesis of dihydrexidine, biomimetic iron(III) mediated oxidative dimerization for synthesis of benzoquinone parvistemin A, enantioselective synthesis of syn-diarylheptanoids from D-glucose, preparation of β-amyloid plaque ligands and decarboxylative cyclopropanation. It react with 4-methyl-oxetan-2-one to produce 4-hydroxy-1-phenyl-1-(triphenyl-l5-phosphanylidene)-pentan-2-one.