Four- vs. five-coordinated intermediates

Group 10 metal alkyls having d electrons may undergo the CO insertion from a four- or five-coordinate intermediate [8]. In a detailed kinetic study concerning the carbonylation, Garrou and Heck proposed two possible insertion pathways via five-coordinate adducts, [MR(CO)(X)L2] (M = Pt, Pd, Ni R 

Involvement of a five-coordinate species during CO insertion was suggested experimentally and theoretically in carbonylation of monoalkylpalladium com- 

The nature of ligands in the reacting complex has a marked effect on the rate of reaction and the insertion pathway. Consequently, a detailed understanding of the 

Another way to achieve introduction of two CO molecules is to convert the initial product of CO insertion into an enolic complex that can further 

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