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A Complementary Process to Pauson-Khand-Type Annulation Reactions for the Construction of Fully Substituted Cyclopentenones.

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 ?-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.

SUBMITTER: Millham AB

PROVIDER: S-EPMC6465167 | biostudies-literature | 2019 Jan

REPOSITORIES: biostudies-literature

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A Complementary Process to Pauson-Khand-Type Annulation Reactions for the Construction of Fully Substituted Cyclopentenones.

Millham Adam B AB Kier Matthew J MJ Leon Robert M RM Karmakar Rajdip R Stempel Zachary D ZD Micalizio Glenn C GC

Organic letters 20190107 2

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 cyclopentenone ...[more]

PMID: 30614709

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