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

Abstract

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.

Keywords:

• Gold(III)
• Alkenes
• Water solution
• DFT calculations

Acknowledgments

The authors thank Dr Jerome Keister and Dr Jeffrey Dudziak for their contributions and Dr Dinesh Sukumaran and Bharathwaj Sathyamoorthy for their invaluable assistance with the NMR experiments. Jochen Autschbach thanks the National Science Foundation (CHE0952253) for financial support of his research. The Spanish agency MICINN is acknowledged for a fellowship to S. Moncho which supported his participation in this project.