Bao M, Lu W, Cai Y, Qiu L, Xu X. Gold(I)-Catalyzed Cyclization/Carbonylation Cascade Reaction of 1,6-Diynes: An Access to β,γ-Unsaturated Ketones.
J Org Chem 2017;
82:13386-13395. [PMID:
29161043 DOI:
10.1021/acs.joc.7b02461]
[Citation(s) in RCA: 12] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/21/2022]
Abstract
A gold-catalyzed cyclization/carbonylation cascade reaction of 1,6-diynes is reported. The reaction goes through 6-exo-dig and 6-endo-dig cyclizations in sequence, followed by hydration to provide the β,γ-unsaturated ketones with moderate to high yields under mild reaction conditions. This is the first example of intercepting the postulated 1,3-oxazine vinylgold intermediate with another pendant alkyne, which not only verifies the proposed mechanism but also provides the ketone products with cyclized 1,2,3,6-tetrahydropyridine or 3,6-dihydro-2H-pyran frameworks from corresponding diynes.
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