| Abstract: | Schiff bases derived from the condensation of β-diketones with N-methyl-S-methyldithiocarbazates yield cis dicarbonyl complexes Rh(CO)2 (Schiff) on reaction with Rh(μ-Cl)(CO)2]2. Those derived from aromatic aldehydes form trans dicarbonyl complexes. These complexes with excess of triphenylphosphine give only Rh(CO)(PPh3)(Schiff). cis-1,5-cyclooctadiene (COD) reacts with cis dicarbonyl complexes to yield the carbonyl-free product Rh(COD)(Schiff); similar reactions have not been observed in the case of trans-dicarbonyl complexes. Oxidative addition of bromine to these complexes yields dibromo derivative in which the Schiff base acts as bidentate chelate. Rh(PPh3)2(Schiff) complexes have been obtained from the reaction of above Schiff bases with Rh(PPh3)3Cl. The structures of these new complexes have been determined based on IR and 1H NMR spectra. |
