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Synthesis of Fulvene Vinyl Ethers by Gold Catalysis.

ABSTRACT: Gold-catalyzed cyclization of 1,5-diynes with ketones as reagents and solvent provides diversely substituted vinyl ethers under mild conditions. The regioselectivity of such gold-catalyzed cyclizations is usually controlled by the scaffold of the diyne. Herein, we report the first solvent-controlled switching of regioselectivity from a 6-endo-dig- to 5-endo-dig-cyclization in these transformations, providing fulvene derivatives. With respect to the functional-group tolerance, aryl fluorides, chlorides, bromides, and ethers are tolerated. Furthermore, the mechanism and selectivity are put to scrutiny by experimental studies and a thermodynamic analysis of the product. Additionally, 6-(vinyloxy)fulvenes are a hitherto unknown class of compounds. Their reactivity is briefly evaluated, to give insights into their potential applications.

SUBMITTER: Ahrens A

PROVIDER: S-EPMC7216831 | biostudies-literature | 2020 Apr

REPOSITORIES: biostudies-literature

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Synthesis of Fulvene Vinyl Ethers by Gold Catalysis.

Ahrens Alexander A Schwarz Julia J Lustosa Danilo M DM Pourkaveh Raheleh R Hoffmann Marvin M Rominger Frank F Rudolph Matthias M Dreuw Andreas A Hashmi A Stephen K ASK

Chemistry (Weinheim an der Bergstrasse, Germany) 20200406 23

Gold-catalyzed cyclization of 1,5-diynes with ketones as reagents and solvent provides diversely substituted vinyl ethers under mild conditions. The regioselectivity of such gold-catalyzed cyclizations is usually controlled by the scaffold of the diyne. Herein, we report the first solvent-controlled switching of regioselectivity from a 6-endo-dig- to 5-endo-dig-cyclization in these transformations, providing fulvene derivatives. With respect to the functional-group tolerance, aryl fluorides, chl ...[more]

PMID: 32092204

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