Mechanism of Rhodium-Catalyzed Carbene Formation from Diazo Compounds
A large and normal nitrogen-15 kinetic isotope effect of 1.035 ± 0.003 provides direct support for the proposed mechanism for the rhodium-catalyzed carbene formation from diazo compounds, which involves the fast formation of a metal−diazo complex followed by rate-limiting extrusion of N2. The large magnitude of the KIE indicates extensive C−N bond fission in the transition state.
Freeman M. Wong, Jianbo Wang, Alvan C. Hengge, and Weiming Wu “Mechanism of Rhodium- Catalyzed Carbene Formation from Diazo Compounds.” Org. Lett.; 2007; 9(9); 1663-1665.