Neutral Cobalt Carbonyl Catalysts for the Equilibration Between CO and P(OPh) 3 Ligands in Carbonylcobaltates

The substitution reaction of [Co(CO) 4 ] − by P(OPh) 3 was investigated in THF. Under a CO atmosphere, the reaction consists of an equilibrium, which, in order to be established, needs [Co 2 (CO) 6 (P(OPh) 3 ) 2 ]. The catalysis by this neutral carbonyl is formally related to a previously reported case, where either [Co 2 (CO) 8 ] or [Co 4 (CO) 12 ] was found to be necessary for the 13 CO scrambling in [Co(CO) 4 ] − . The kinetic analysis reported in this paper indicates, however, that the two CO labilizations differ in their mechanism‐the substitution by P(OPh) 3 is ascribed to a disproportionation‐synproportionation of [Co 2 (CO) 6 (P(OPh) 3 ) 2 ].