Addition of aluminium, zinc and magnesium hydrides to rhodium(III)

Abstract

We report the addition of M-H bonds (M = Al, Zn, Mg) to a Rh(iii) intermediate generated from the reductive elimination of triethylsilane from [Cp∗Rh(H) 2 (SiEt 3) 2 ]. A series of new heterobimetallic complexes possessing Rh-M bonds have been isolated and characterised by a number of spectroscopic ( 1 H, 29 Si, 13 C, 103 Rh NMR, infrared, and X-ray diffraction) and computational techniques (NBO and QTAIM analysis). Experimental and computational data are consistent with cleavage of the M-H bond upon addition to rhodium with formation of new Rh-M and Rh-H bonds. Upon photolysis the Al analogue of this series undergoes a further elimination reaction producing triethylsilane and a highly unusual Rh 2 Al 2 H 4 containing cluster proposed to contain an Al(i) bridging ligand.