Cone angle ligand displacement

Steric effects play a role in the rate of ligand displacement. The rate of reaction for equation 7.13 has been measured for a number of phosphine ligands (PR3), and the results indicate that the rate of substitution is accelerated by bulky phosphines. A good correlation between cone angle (see Section 6-3) of the phosphine (or phosphite) ligand and rate of displacement by CO was obtained, as shown in Table 7-3. 

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