Heterobimetallic catalysis

[11] A chiral bisphosphine-ligated rhodium catalyst activates the alpha-keto-nitrile component as its corresponding enolate, which is intercepted by a π-allylpalladium complex to yield the α-allylated nitrile in high enantiomeric excess.

The incorporation of copper into the catalyst is essential; C-H borylation using (pin)B-Fp alone is stoichiometric in iron due to dimerization of the HFp byproduct.

Heterobimetallic catalysts containing persistent M1-M2 bonds exhibit altered reactivity due to interaction of the two different metal centers.

[16] DFT studies suggest that a Pd→Ti dative interaction accelerates the typically slow reductive elimination step by withdrawing electron density from Pd in the transition state[17] (Scheme 6).

The calculations have shown that steric effects imparted by the ancillary ligands could result in enormous differences in C-H activation energy barriers (ca.

The resulting NiIII-amido rapidly undergoes reductive elimination,[20] allowing the Ni-catalyzed aryl amination to proceed at room temperature without the use of phosphine ligands.

Enzymes containing two or more different metal centers are found in several important biological systems; for example, the Mo-Fe protein of nitrogenase[21] catalyzes the conversion of N2 to NH3 in nitrogen fixation.