Gold catalysis.

Catalysis by gold has rapidly become a hot topic in chemistry, with a new discovery being made almost every week. Gold is equally effective as a heterogeneous or a homogeneous catalyst and in this Review we attempt to marry these two facets to demonstrate this new found and general efficacy of gold. The latest discoveries are placed within a historical context, but the main thrust is to highlight the new catalytic possibilities that gold-catalyzed reactions currently offer the synthetic chemist, in particular in redox reactions and nucleophilic additions to pi systems. Indeed gold has proved to be an effective catalyst for many reactions for which a catalyst had not been previously identified, and many new discoveries are still expected.