Wolff Rearrangement

L. Wolff Ann. 394, 25 (1912).

Rearrangement of diazoketones to ketenes thermally, photochemically or catalytically. The rearrangement is the key step in the Arndt-Eistert synthesis, q.v.:

Reviews: P. A. S. Smith in Molecular Rearrangements Part 1, Ed. (Wiley-Interscience, New York, 1963) pp 528-550, 558-568; W. Kirmse, Carbene Chemistry (Academic Press, New York, 2nd ed., 1971) pp 475-492; H. Meier, K. P. Zeller, Angew. Chem. Int. Ed. 14, 32 (1975); M. Torres, Pure Appl. Chem. 52, 1623 (1980); C. B. Gill, Comp. Org. Syn. 3, 887-912 (1991). Photo-induced mechanistic studies: T. Lippert et al., J. Am. Chem. Soc. 118, 1551 (1996); Y. Chiang et al., ibid. 121, 5930 (1999). Synthetic application: Y. R. Lee et al., Tetrahedron Letters 40, 8219 (1999).