Oxalato complexes of Re(V). Synthesis and structural characterization of [ReO(OCH3)(ox)(L)] (L=bipy, dppe and dppee)

Two kinds of optically active hydrazides reacted with three tetrahedron-type clusters, respectively, to form hydrazone cluster diastereoisomers, intending to separate racemic clusters. However, the mixture of diastereoisomers cannot be separated into single diastereoisomer by silica gel chromatography. The 1H and 13C NMR spectra established their presence.