Gold-Catalyzed Intermolecular Anti-Markovnikov Hydroamination of Alkylidenecyclopropanes

The cationic gold phosphine complex [{PCy2(o-biphenyl)} Au(NCMe)]+SbF6- (Cy = cyclohexyl) catalyzes the intermolecular, anti-Markovnikov hydroamination reaction of monosubstituted and cis- and trans-disubstituted alkylidene-cyclopropanes (ACPs) with imidazolidin-2-ones and other nucleophiles. This reaction forms 1-cyclopropyl alkylamine derivatives in high yield and with high regio- and diastereo-selectivity. NMR spectroscopic analysis of gold pi-ACP complexes and control experiments point to the sp hybridization of the ACP internal alkene carbon atom as controlling the regiochemistry of the ACP hydroamination reaction.