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Copper-Catalyzed Vinylogous Aerobic Oxidation of Unsaturated Compounds with Air.

ABSTRACT: A mild and operationally simple copper-catalyzed vinylogous aerobic oxidation of ?,?- and ?,?-unsaturated esters is described. This method features good yields, broad substrate scope, excellent chemo- and regioselectivity, and good functional group tolerance. This method is additionally capable of oxidizing ?,?- and ?,?-unsaturated aldehydes, ketones, amides, nitriles, and sulfones. Furthermore, the present catalytic system is suitable for bisvinylogous and trisvinylogous oxidation. Tetramethylguanidine (TMG) was found to be crucial in its role as a base, but we also speculate that it serves as a ligand to copper(II) triflate to produce the active copper(II) catalyst. Mechanistic experiments conducted suggest a plausible reaction pathway via an allylcopper(II) species. Finally, the breadth of scope and power of this methodology are demonstrated through its application to complex natural product substrates.

SUBMITTER: Zhang HJ

PROVIDER: S-EPMC5927363 | biostudies-literature | 2018 Apr

REPOSITORIES: biostudies-literature

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Copper-Catalyzed Vinylogous Aerobic Oxidation of Unsaturated Compounds with Air.

Zhang Hai-Jun HJ Schuppe Alexander W AW Pan Shi-Tao ST Chen Jin-Xiang JX Wang Bo-Ran BR Newhouse Timothy R TR Yin Liang L

Journal of the American Chemical Society 20180409 15

A mild and operationally simple copper-catalyzed vinylogous aerobic oxidation of β,γ- and α,β-unsaturated esters is described. This method features good yields, broad substrate scope, excellent chemo- and regioselectivity, and good functional group tolerance. This method is additionally capable of oxidizing β,γ- and α,β-unsaturated aldehydes, ketones, amides, nitriles, and sulfones. Furthermore, the present catalytic system is suitable for bisvinylogous and trisvinylogous oxidation. Tetramethylg ...[more]

PMID: 29547276

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