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Synthesis of six-membered spirooxindoles via a chiral Bronsted acid-catalyzed asymmetric intramolecular Friedel-Crafts reaction.

ABSTRACT: By means of the direct condensation of N-aminoethylpyrroles and isatins, followed by a chiral phosphoric acid-catalyzed asymmetric intramolecular Friedel-Crafts reaction, a new class of valuable chiral 3',4'-dihydro-2'H-spiro[indoline-3,1'-pyrrolo[1,2-a]pyrazin]-2-ones bearing a quaternary carbon stereocenter were successfully synthesized in good to excellent yields and with moderate to good enantioselectivities under mild reaction conditions.

SUBMITTER: Chen HX

PROVIDER: S-EPMC9089239 | biostudies-literature | 2018 Nov

REPOSITORIES: biostudies-literature

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Synthesis of six-membered spirooxindoles via a chiral Brønsted acid-catalyzed asymmetric intramolecular Friedel-Crafts reaction.

Chen Hui-Xuan HX Zhang Yaqi Y Zhang Yuyang Y He Xuefeng X Zhang Zhen-Wei ZW Liang Hao H He Wenhuan W Jiang Xiaoding X Chen Xiangmeng X Qiu Liqin L

RSC advances 20181101 65

By means of the direct condensation of N-aminoethylpyrroles and isatins, followed by a chiral phosphoric acid-catalyzed asymmetric intramolecular Friedel-Crafts reaction, a new class of valuable chiral 3',4'-dihydro-2'H-spiro[indoline-3,1'-pyrrolo[1,2-a]pyrazin]-2-ones bearing a quaternary carbon stereocenter were successfully synthesized in good to excellent yields and with moderate to good enantioselectivities under mild reaction conditions. ...[more]

PMID: 35557774

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