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PubMed · 10990414

Intramolecular ketene-allene cycloadditions.

K L McCaleb·R L Halcomb
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Abstract

[reaction: see text]This report describes intramolecular thermal [2 + 2] cycloadditions between ketenes and allenes. The formation of ketenes and the subsequent cycloadditions occurred under a variety of conditions, affording 7-methylidinebicyclo[3.2.0]heptanones and 7-methylidinebicyclo[3.1.1]heptanones in 45-78% yields. The regioselectivity of the cycloaddition varied with the substitution of the allene, and the yield of cyclized products varied with reaction conditions.

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AlkenesBridged Bicyclo CompoundsCyclizationIndicators and ReagentsMagnetic Resonance SpectroscopySpectrophotometry, InfraredSpectrophotometry, UltravioletStereoisomerismJournal ArticleResearch Support, Non-U.S. Gov'tResearch Support, U.S. Gov't, Non-P.H.S.Research Support, U.S. Gov't, P.H.S.

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K L McCaleb, R L Halcomb. 2000-08-24. Intramolecular ketene-allene cycloadditions.. https://doi.org/10.1021/ol000145a

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