O/C bond cleavage of CO2 by NiI

Reaction of (PNP)Ni, where PNP is [((Bu2PCH2SiMe2)-Bu-t)(2)N](-1), with CO2 occurs rapidly even at -60 degrees C to form exclusively the product of transposition of the amide N and one CO2 oxygen: [((Bu2PCH2)-Bu-t SiMe2)(2)O]Ni(NCO). DFT(B3LYP) evaluation of several candidate intermediates for breaking two Si/N and one C/O bond and forming two Si/O and one N/C bond reveal species at and below the energy of the separated particles, and establish, the location of the spin densities in each.