Preparation, properties, and crystal and molecular structures of bis(dialkylamine) complexes of rhenium(I)

Abstract

The crystal and molecular structures of the two bis(amine) complexes of rhenium(I), [ReBr(CO)₃(NHR₂)₂](R = Me or Et), have been studied by X-ray diffraction methods. The complexes crystallize in the monoclinic system, space group P2₁/n, with cell constants (R = Me)a= 9.023(3), b= 11.537(4), c= 12.199(4)Å, β= 97.28(3)°; and (R = Et)a= 7.340(2), b= 9.784(3), c= 22.742(6)Å, β= 95.05(2)°. The molecular structure in both cases consists of facially arranged ligands around six-co-ordinate rhenium(I); the two cis amine ligands do not interact appreciably either by intra- or inter-molecular hydrogen bonding. The ethyl derivative reacts with CO₂ to give the corresponding carbamato-complex [Re(CO)₃(O₂CNEt₂)(NHEt₂)], the latter showing association in solution presumably due to intermolecular hydrogen bonding.