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A Complementary Process to Pauson-Khand-Type Annulation Reactions for the Construction of Fully Substituted
Adam B Millham1, Matthew J Kier1, Robert M Leon1
1Department of Chemistry , Dartmouth College , Burke Laboratory, Hanover , New Hampshire 03755 , United States.
Abstract:
A complementary process to the Pauson-Khand annulation is described that is well suited to forging densely substituted/oxygenated cyclopentenone products (including fully substituted variants). The reaction is thought to proceed through a sequence of metallacycle-mediated bond-forming events that engages an internal alkyne and a β-keto ester in an annulation process that forges two C-C bonds. A variant of this annulation process has also been established that delivers deoxygenated cyclopentenones that lack the allylic tertiary alcohol.
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