The reaction may or may not proceed in a concerted mechanism. A carbene intermediate is avoided if the reaction proceeds through the concerted mechanism. Mechanistic studies have been aimed at determining if migration is concerted with loss of nitrogen. The conclusion that has emerged is that a carbene is generated in photochemical reactions but the reaction can be concerted under the thermal conditions.
In one application,[7] the Wolff rearrangement is performed in an electrochemical setup in which the catalyst silver oxide is reduced to elemental silver in the shape of monodisperse nanoparticles (2-4 nm diameter) which trigger the decomposition of the diazoketone by the formation of a radical cation.
^ Wheeler, T. N.; Meinwald, J. Org. Syn., Coll. Vol. 6, p.840 (1988); Vol. 52, p.53 (1972) (Article)
^ Smith, L. I.; Hoehn, H. H. Org. Syn., Coll. Vol. 3, p.356 (1955); Vol. 20, p.47 (1940) (Article)
^Wolff Rearrangement of -Diazoketones Using in Situ Generated Silver Nanoclusters as Electron Mediators Surendra G. Sudrik, Jadab Sharma, Vilas B. Chavan, Nirmalya K. Chaki, Harikisan R. Sonawane, and Kunjukrishna P. Vijayamohanan Org. Lett.2006, 8(6), 1089-1092. (doi:10.1021/ol052981w)
