A study of the co-ordination behaviour of the chalcogenocyanate ions

The coordination behaviour of the pseudohalide ions (NCO¯ NCS¯ NCSe¯ NCTe¯) has been studied. A number of N- and S-bonded thiocyanate complexes of rhodium(I), of the type Rh(PPh3)2(L)CNS (L = ligand), have been prepared. The mode of linkage of the thiocyanate group has been established by means of infrared spectral measurements. The preparation of Rh(PPh3)2(piperidine)NCS clearly demonstrates that a strongly π-accepting ligand such as CO is not a prerequisite for a N-thiocyanato complex of the type Rh(PPh3)2(L)NCS. [Continues.]