ABSTRACT
Metal complexes have also been used as catalysts for CO2 reduction, but only few examples are known where the major product is oxalate [148 and refs. therein]. The reductions are inner-sphere processes, and oxalate formation takes place at significantly higher potentials than, by direct reduction or reduction via organic catalysts (which typically have values of E0 in the range -1.95 V to -2.25 V). Catalytic dimerization of CO2 in MeCN has been reported to take place at - l.5 V using the complex [(RhCp*MµrShJ2+, at -0.7 V using the complex [(CoCp*h(µrSh]2+, and at -1.6 V using [(lrCp*h(µ, 3 - ShJ2+ [148).
