Reactions of gold(III) complexes with alkenes in aqueous media: generation of bis-(β-hydroxyalkyl)gold(III) complexes

Reactions of gold(III) complexes with ethylene and propylene in water provide the first such examples not accompanied by reduction of the gold. HAuCl4 and AuCl3(TPPTS) produce organic products (alcohol, aldehyde/ketone, etc.) with gold reduction to the metal. However, [Au(bipy)Cl2]Cl in water produces the gold(III) β-hydroxy complexes, [Au(bipy)(CH2CH2OH)2]X (X = Cl−, PF6 −) and [Au(bipy)(CH2CH(OH)CH3]Cl, which are stable in solution. These complexes could not be isolated, but were characterized by NMR and high-resolution mass spectra. [Au(terpy)Cl]Cl2 fails to react with ethylene in water, even at elevated temperatures. DFT computations were performed to investigate the reaction mechanism.