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Mechanism of a Dually Catalyzed Enantioselective Oxa-Pictet-Spengler Reaction and the Development of a Stereodivergent Variant.

ABSTRACT: Enantioselective oxa-Pictet-Spengler reactions of tryptophol with aldehydes proceed under weakly acidic conditions utilizing a combination of two catalysts, an indoline HCl salt and a bisthiourea compound. Mechanistic investigations revealed the roles of both catalysts and confirmed the involvement of oxocarbenium ion intermediates, ruling out alternative scenarios. A stereochemical model was derived from density functional theory calculations, which provided the basis for the development of a highly enantioselective stereodivergent variant with racemic tryptophol derivatives.

SUBMITTER: Adili A

PROVIDER: S-EPMC10501388 | biostudies-literature | 2023 Feb

REPOSITORIES: biostudies-literature

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Mechanism of a Dually Catalyzed Enantioselective Oxa-Pictet-Spengler Reaction and the Development of a Stereodivergent Variant.

Adili Alafate A Webster John-Paul JP Zhao Chenfei C Mallojjala Sharath Chandra SC Romero-Reyes Moises A MA Ghiviriga Ion I Abboud Khalil A KA Vetticatt Mathew J MJ Seidel Daniel D

ACS catalysis 20230127 4

Enantioselective oxa-Pictet-Spengler reactions of tryptophol with aldehydes proceed under weakly acidic conditions utilizing a combination of two catalysts, an indoline HCl salt and a bisthiourea compound. Mechanistic investigations revealed the roles of both catalysts and confirmed the involvement of oxocarbenium ion intermediates, ruling out alternative scenarios. A stereochemical model was derived from density functional theory calculations, which provided the basis for the development of a h ...[more]

PMID: 37711191

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