POLAROGRAPHIC BEHAVIOR OF TRANSITION METAL NITROSYL COMPLEXES IN NON-AQUEOUS MEDIA .2. MONO- AND DISUBSTITUTED DERIVATIVES OF NITROSYLTRICARBONYL-COBALT WITH PHOSPHINE- ARSINE- AND STIBI-LIGANDS

Some mono- and disubstituted derivatives of nitrosyltricarbonyleobalt are studied polarographically. Their behavior is characteristic both of the degree of substitution and of the type of substituent ligands. The half-wave potential for the production of the primary radical anion increases with the basicity of entering ligands and with their number. The overall reduction mechanism appears to depend only on the degree of substitution; this is also responsible for a drastic decrease of adsorption ability at the electrode of these molecules, found on going from the parent complex Co(CO)3NO down to its mono- and disubstituted derivatives. The experimental results are discussed interms of the electronic structure of these complexes. A comparison with the parent complex indicates that the orbital mainly interested in the electron transfer process is themore delocalized from the NO group to the whole molecule, the higher the substitution degree. © 1968, Walter de Gruyter. All rights reserved.