Eschenmoser Fragmentation (Eschenmoser-Tanabe Fragmentation)

A. Eschenmoser et al., Helv. Chim. Acta 50, 708 (1967); J. Schreiber et al., ibid. 2101; M. Tanabe et al., Tetrahedron Letters 1967, 3943.

Cleavage of α,β-epoxyketones under mild conditions, via sulfonylhydrazone intermediates, to yield acetylenic and carbonyl compounds:



Early review: D. Felix et al., Helv. Chim. Acta 54, 2896-2912 (1971). Synthetic applications: C. B. Reese, H. P. Sanders, Synthesis 1981, 276; W. Dai, J. A. Katzenellenbogen, J. Org. Chem. 58, 1900 (1993); A. Abad et al., Synlett 1991, 787. Cf. Grob Fragmentation; Wharton Reaction.