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Enantioselective Tandem Cyclization of Alkyne-Tethered Indoles Using Cooperative Silver(I)/Chiral Phosphoric Acid Catalysis.

ABSTRACT: Reported is the enantioselective synthesis of tetracyclic indolines using silver(I)/chiral phosphoric acid catalysis. A variety of alkyne-tethered indoles are suitable for this process. Mechanistic studies suggest that the in?situ generated silver(I) chiral phosphate activates both the alkyne and the indole nucleophile in the initial cyclization step through an intermolecular hydrogen bond and the phosphate anion promotes proton transfer. In addition, further modifications of the cyclization products enabled stereochemistry-function studies of a series of bioactive indolines.

SUBMITTER: Zhu Y

PROVIDER: S-EPMC5997581 | biostudies-literature | 2017 Sep

REPOSITORIES: biostudies-literature

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Enantioselective Tandem Cyclization of Alkyne-Tethered Indoles Using Cooperative Silver(I)/Chiral Phosphoric Acid Catalysis.

Zhu Yugen Y He Wei W Wang Wei W Pitsch Chloe E CE Wang Xiaotai X Wang Xiang X

Angewandte Chemie (International ed. in English) 20170823 40

Reported is the enantioselective synthesis of tetracyclic indolines using silver(I)/chiral phosphoric acid catalysis. A variety of alkyne-tethered indoles are suitable for this process. Mechanistic studies suggest that the in situ generated silver(I) chiral phosphate activates both the alkyne and the indole nucleophile in the initial cyclization step through an intermolecular hydrogen bond and the phosphate anion promotes proton transfer. In addition, further modifications of the cyclization pro ...[more]

PMID: 28746772

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