Cooperative strategies for CO homologation.

Recent approaches in which at least two metal or main-group centres are involved in the homologation of CO are reviewed. We have characterised the strategies into three broad areas: (i) the reductive homologation of atmospheric CO at a metal or main group centre (ii) the reductive homologation of metal-carbonyl CO units and (iii) reductive homologation of CO with M-M, B-Li, Si[double bond, length as m-dash]Si, and B[triple bond, length as m-dash]B bonds.