Studies on gold-nitrone systems.

A series of novel Au(i)-nitrone complexes with specific catalytic properties were prepared. Furthermore, Au(i)- and Au(iii)-oxadiazole complexes were formed by a novel Au-generated nitrile-nitrone [3 + 2] cycloaddition, and the crystal structures of Au(i)-nitrones as well as the Au(i)- and Au(iii)-oxadiazole complexes were studied (X-ray). A useful one-pot Au(iii)-mediated cycloaddition method was developed for the formation of a number of dihydro-1,2,4-oxadiazoles, involving in situ formation of Au(iii)-oxadiazole complexes. The observed Au(i) and Au(iii) dual selective reactivity gives new understanding about the Au(i)- and Au(iii)-nitrone chemistry.