RUPE Rearrangement

Acid-catalyzed rearrangement of tertiary a-acetylenic (terminal) alcohols, leading to the formation of a,(3-unsaturated ketones rather than the corresponding a,(3-unsaturated aldehydes. Cf. Meyer-Schuster rearrangement. 

Name Reactions, 4th ed., DOI10.1007/978-3-642-01053-8 224, Springer-Verlag Berlin Heidelberg 2009 

MuUins, R. J. ColUns, N. R. Meyer-Schuster Rearrangement, la Name Reactions for Homologations-Part II Li, J. J., Corey, E. J., Eds. Wiley Sons Hoboken, NJ, 2009, pp 305—318. (Review). 

Na/ne Reactions A Collection of Detailed Mechanisms and Synthetic Applications, DOI 10.1007/978-3-319-03979-4 239, Springer International Publisliing Switzerland 2014 

Schade, C. Will, E. Koschinsky, R. Bauml, E. Mayr, H. Tetra-hedron 1988, 44,2181-2184. 

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The products from the acid-catalyzed hydration of a-tertiary alcohols 30 (Meyer-Schuster and Rupe rearrangements) are formed via the mesomeric propargyl-allenyl cation (equation 9) and have been extensively investigated28. 

When 2-ethynyl-2-hydroxyadamantane (31) was treated with 95% formic acid or dilute sulfuric acid only a Meyer-Schuster rearrangement took place to give 95% of 2-(formylmethylene)adamantane (32) (equation 10). No Rupe rearrangement took place29. 

Capnellane is the generic name applied to a group of sesquiterpene alcohols and the hydrocarbon isolated from the soft coral Capnella imbricata A < >-Capnellene (667), the presumed biosynthetic precursor of the capnellenols, was first synthesized in 1981 by Stevens and Paquette Their synthetic plan called for the construction of bicyclic ketone 668 and its appropriate annulation. The latter event was achieved by application of the Rupe rearrangement to 668, conjugate addition of a vinyl group to 669, ozonolysis, and cyclization (Scheme LXVIII). Hydrogenation and olefination completed the sequence. 

The Mever-Schuster Rearraneement is similar to the Rupe Rearrangement. 

The hydration of conjugated diynes readily affords 1,3-diketones. The hydration may be acid- or mercuric sulfate-catalyzed. The Rupe rearrangement is observed under general acid catalysis (equation 204).310... 

Alkynes may participate in a number of rearrangement reactions, exemplified by the Rupe rearrangement of ethynylcyclohexanol to an unsaturated ketone (Scheme 3.31). 

RUFF FENTON Degradation 327 RUPE Rearrangement 328 RUZICKA FUKUSHIMA Rearrangement 3 Rylander 97... 

Olah, G. A., Rung, A. P. Synthetic methods and reactions 98. Improved solid super acid (Nafion-H) catalyzed Rupe rearrangement of a-ethynyl alcohols to a,P-unsaturated carbonyl compounds. Synfhes/s 1981,473-474. 

Weinmann, H., Harre, M., Neh, H., Nickisch, K., Skoetsch, C., Tilstam, U. The Rupe Rearrangement A New Efficient Method for Large-Scale Synthesis of Unsaturated Ketones in the Pilot Plant. Org. Process Res. Dev. 2002, 6, 216-219. 

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