256.

Meyer-Schuster Rearrangement; Rupe Rearrangement

K. H. Meyer, K. Schuster, Ber. 55, 819 (1922); H. Rupe, E. Kambli, Helv. Chim. Acta 9, 672 (1926).

Acid-catalyzed rearrangement of secondary and tertiary α-acetylenic alcohols to α,β-unsaturated carbonyl compounds: aldehydes result when the acetylenic group is terminal, ketones when it is internal:

The conversion of tertiary alkylacetylenic carbinols with a terminal acetylenic group to predominantly α,β-unsaturated ketones and not the expected aldehydes, is referred to as the Rupe rearrangement:

Metal-based catalysis: P. Chabardes, Tetrahedron Lett. 29, 6253 (1988); C. Y. Lorber, J. A. Osborn, ibid. 37, 853 (1996). Mechanism studies: M. Edens et al., J. Org. Chem. 42, 3403 (1977); J. Andres et al., J. Am. Chem. Soc. 110, 666 (1988). Applications: E. A. Omar et al., J. Heterocycl. Chem. 29, 947 (1992); M. Yoshimatsu et al., J. Org. Chem. 60, 4798 (1995). Early reviews: R. Heilmann, R. Glenat, Ann. Chim. (Paris) 8, 178 (1963); S. Swaminathan, K. V. Narayanan, Chem. Rev. 71, 429 (1971).