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Preparation of spiro[indole-3,5'-isoxazoles] via Grignard conjugate addition/spirocyclization sequence.

ABSTRACT: A highly efficient one-pot procedure combining conjugate addition of Grignard reagents to (2-nitroalkenyl)indoles and sub-sequent Brønsted acid-assisted spirocyclization allowed for preparation of 4'H-spiro[indole-3,5'-isoxazoles] in a diastereomerically selective fashion. Utilization of alkyl Grignard reagents provided an easy access to 4'-alkylsubstituted derivatives hardly available by other means.

SUBMITTER: Aksenov AV

PROVIDER: S-EPMC8693578 | biostudies-literature | 2021 Jan

REPOSITORIES: biostudies-literature

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Preparation of spiro[indole-3,5'-isoxazoles] <i>via</i> Grignard conjugate addition/spirocyclization sequence.

Aksenov Alexander V AV Aksenov Dmitrii A DA Aksenov Nicolai A NA Skomorokhov Anton A AA Aleksandrova Elena V EV Rubin Michael M

RSC advances 20210106 3

A highly efficient one-pot procedure combining conjugate addition of Grignard reagents to (2-nitroalkenyl)indoles and sub-sequent Brønsted acid-assisted spirocyclization allowed for preparation of 4'<i>H</i>-spiro[indole-3,5'-isoxazoles] in a diastereomerically selective fashion. Utilization of alkyl Grignard reagents provided an easy access to 4'-alkylsubstituted derivatives hardly available by other means. ...[more]

PMID: 35424118

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