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Gold-catalyzed cyclization of allenyl acetal derivatives.

ABSTRACT: The gold-catalyzed transformation of allenyl acetals into 5-alkylidenecyclopent-2-en-1-ones is described. The outcome of our deuterium labeling experiments supports a 1,4-hydride shift of the resulting allyl cationic intermediates because a complete deuterium transfer is observed. We tested the reaction on various acetal substrates bearing a propargyl acetate, giving 4-methoxy-5-alkylidenecyclopent-2-en-1-ones 4 via a degradation of the acetate group at the allyl cation intermediate.

SUBMITTER: Vasu D

PROVIDER: S-EPMC3778408 | biostudies-literature | 2013

REPOSITORIES: biostudies-literature

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Gold-catalyzed cyclization of allenyl acetal derivatives.

Vasu Dhananjayan D Pawar Samir Kundlik SK Liu Rai-Shung RS

Beilstein journal of organic chemistry 20130827

The gold-catalyzed transformation of allenyl acetals into 5-alkylidenecyclopent-2-en-1-ones is described. The outcome of our deuterium labeling experiments supports a 1,4-hydride shift of the resulting allyl cationic intermediates because a complete deuterium transfer is observed. We tested the reaction on various acetal substrates bearing a propargyl acetate, giving 4-methoxy-5-alkylidenecyclopent-2-en-1-ones 4 via a degradation of the acetate group at the allyl cation intermediate. ...[more]

PMID: 24062838

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