WATER-SOLUBLE CO3C AND CO2C2 CLUSTERS - REDOX CHEMISTRY AND ELECTROCHEMICAL REACTIONS IN WATER

The water-soluble clusters [Co3(CR)(CO)8L]n- {n = 1 or 3, L = [PPh3-n( C6H4SO3-M)n]n-; R = Ph, Me, Cl or Br) and [Co2{C2(CO2Me)2}(CO)5{P(C6H4 SO3-M)3}]3- (two isomers) have been prepared and characterised. Attemp ts were also made to sulfonate the capping aryl group of [Co3(CPh)(CO) 9]. The redox processes of these complexes in water, 'wet' and 'dry' s olvents have been investigated; E over arrow pointing right C E over a rrow pointing right and E over arrow pointing right C E over arrow poi nting right mechanisms, similar to those elucidated for non-aqueous so lvents, operate in water but the large sulfonated ligands influence th e kinetic parameters. The need to use dry solvents for electrochemical studies of these clusters may not be as important as previously thoug ht.