Synthesis 2024; 56(05): 828-850
DOI: 10.1055/a-2223-3803
paper

Stereoselective Construction of Vicinal Quaternary Stereocenters via the 1,6-Conjugate Addition of β,β-Disubstituted N-Sulfinyl Metalloenamines to Isatin-Derived para-Quinone Methides

Autoren

  • Zheng-Fei Li

    a   School of Chemical Science and Technology, Yunnan University, Kunming, Yunnan 650091, P. R. of China
  • Chong-Dao Lu

    a   School of Chemical Science and Technology, Yunnan University, Kunming, Yunnan 650091, P. R. of China
    b   School of Health, Jiangxi Normal University, Nanchang, Jiangxi 330022, P. R. of China

This work was supported by the National Natural Science Foundation of China (22361049 and 22161048) and the ‘Double Thousand Plan’ of Jiangxi Province (JXSQ2023102241).


Graphical Abstract

Abstract

A 1,6-conjugate addition reaction of β,β-disubstituted N-tert-butanesulfinyl metalloenamines, generated via stereospecific α-deprotonation of enantioenriched α,α-disubstituted ketimines or deprotonation of the NH in geometry-defined enesulfinamides, with isatin-derived para-quinone methides is developed to build vicinal quaternary stereocenters with high stereocontrol. The resulting 3,3-disubstituted oxindoles contain a less-accessible acyclic quaternary stereogenic carbon substituted with two sterically and electronically similar groups at the α-position of the imino group. This protocol constitutes a rare example of the stereoselective construction of vicinal quaternary stereocenters via the conjugate addition of acyclic enolates/aza-enolates bearing two similar β-substituents.

Supporting Information



Publikationsverlauf

Eingereicht: 13. November 2023

Angenommen nach Revision: 06. Dezember 2023

Accepted Manuscript online:
06. Dezember 2023

Artikel online veröffentlicht:
16. Januar 2024

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