Ab-initio SCF potential energy surfaces for the nucleophilic attack of hydride on coordinated carbon monoxide

Ab-initio SCF calculations are reported for the nucleophilic addition of the hydride ion H⁻ on the iron pentacarbonyl Fe(CO)₅ complex. The stereochemistry of the attack has been established from the determination of two potential energy surfaces. The reaction is shown to be highly exothermic and with no activation barrier. This activation of CO towards the nucleophilic addition is rationalized in terms of molecular orbital interactions.