Gold(I) complexes containing the cationic ylide ligand bis(methyldiphenylphosphonio)methylide

Abstract

The ylide Ph 2PCHPPh 2Me can be selectively P-alkylated by MeI or MeO 3SCF 3 to form the bis(methyldiphenylphosphonio)methylide salts [MePPh 2CHPPh 2Me]A (AI ( 1), CF 3SO 3 ( 2)). The ylidic carbon shows a weak nucleophilicity and does not give typical reactions with common organic electrophiles, including Wittig type reactions, but it is able to displace tetrahydrothiophene in [AuX(tht)] to give the corresponding C-coordinated gold(I) compounds [Au{CH(PPh 2Me) 2}X]CF 3SO 3 (XCl ( 3), C 6F 5 ( 4)). The crystal structure of ( 4) displays a linear coordination for the gold atom, single PC bond lengths and a PCP angle of 119.1(3)° for the ligand.