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Tosylhydrazine-promoted self-conjugate reduction-Michael/aldol reaction of 3-phenacylideneoxindoles towards dispirocyclopentanebisoxindole derivatives.

ABSTRACT: An efficient tosylhydrazine-mediated conjugate reduction of 3-phenacylideneoxindole and sequential Michael/intramolecular aldol reaction is reported under base-catalyzed conditions towards the formation of densely substituted dispirocyclopentanebisoxindole derivatives. The reaction proceeded in a diastereoselective manner to afford four chiral stereocenters. The method also has advantages of wide substrate scope, readily available starting materials and operational simplicity through one pot reaction.

SUBMITTER: Pramanik S

PROVIDER: S-EPMC9062653 | biostudies-literature | 2022

REPOSITORIES: biostudies-literature

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Tosylhydrazine-promoted self-conjugate reduction-Michael/aldol reaction of 3-phenacylideneoxindoles towards dispirocyclopentanebisoxindole derivatives.

Pramanik Sayan S Mukhopadhyay Chhanda C

Beilstein journal of organic chemistry 20220427

An efficient tosylhydrazine-mediated conjugate reduction of 3-phenacylideneoxindole and sequential Michael/intramolecular aldol reaction is reported under base-catalyzed conditions towards the formation of densely substituted dispirocyclopentanebisoxindole derivatives. The reaction proceeded in a diastereoselective manner to afford four chiral stereocenters. The method also has advantages of wide substrate scope, readily available starting materials and operational simplicity through one pot rea ...[more]

PMID: 35558650

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