Studies on a new class of organobimetallic compounds

Abstract Organometallic compounds of general formula (SCN) 2 Ni(NCSHgR) 2 (R = CH 3 , C 2 H 5 , n-C 4 H 9 and iso-C 4 H 9 ) have been synthesized. These organometallic compounds behave as Lewis acids and form complexes with pyridine, nicotinamide and 2,2'-bipyridyl. The Lewis acids and the complexes are characterized by elemental analysis, molecular weight determination, molar conductance, IR spectral (4000-50 cm −1 ), electronic spectral and magnetic susceptibility measurements. These studies indicate that Lewis acids are monomeric in nature having bridging thiocyanate between Ni 2+ and Hg 2+ . Nickel acquires octahedral configuration through axial bridging, whereas mercury retains its linearity. Pyridine and nicotinamide link at nickel of the Lewis acid and form adducts of formula L 2 (SCN) 2 Ni(NCSHgR) 2 . Bipyridyl ruptures the thiocyanate bridge and forms cationic-anionic complexes [Ni(bipy) 3 ] [(NCS) 2 HgR] 2 . Softness values are also used in a novel manner in proposing the structures of the complexes and in suggesting the relative behaviour of the Lewis acids.