Selective homogeneous and heterogeneous gold catalysis with alkynes and alkenes: Similar behavior, different origin

The development of new sustainable chemical processes requires the implementation of ultra-selective reaction processes. The enormous selectivity found for gold-based catalysts when applied in several reactions has opened new frontiers. For instance, the selective activation of alkynes is a common feature for both homogeneous and heterogeneous gold catalysts. Herein, we employ experimental and theoretical methods to assess the similarities and differences in the performance of homogeneous and heterogeneous gold catalysts. Alkynophilicity, the selective activation of alkynes, is found to have a thermodynamic origin in the heterogeneous case and a kinetic one for homogeneous catalysis. Complex enyne rearrangements require the more active homogeneous (single gold) catalyst because it has more electrophilic character than its heterogeneous (nanoparticle) counterpart. © 2008 Wiley-VCH Verlag GmbH & Co. KGaA.