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Differentiating Catalysis in the Dearomative [4 + 2]-Cycloaddition Involving Enals and Heteroaromatic Aldehydes.

ABSTRACT: In this paper, the application of differentiating catalysis in the [4 + 2]-cycloaddition between 2-alkyl-3-formylheteroarenes and α,β-unsaturated aldehydes is described. Within the developed approach, the same aminocatalyst is employed for the independent activation of both starting materials, differentiating their properties via LUMO-lowering and HOMO-rising principles. By the combination of dearomative dienamine activation with iminium ion chemistry high enantio- and diastereoselectivity of the doubly asymmetric process was accomplished. Selected transformations of products were also demonstrated.

SUBMITTER: Topolska A

PROVIDER: S-EPMC8805123 | biostudies-literature | 2022 Jan

REPOSITORIES: biostudies-literature

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Differentiating Catalysis in the Dearomative [4 + 2]-Cycloaddition Involving Enals and Heteroaromatic Aldehydes.

Topolska Aleksandra A Frankowski Sebastian S Albrecht Łukasz Ł

Organic letters 20220118 3

In this paper, the application of differentiating catalysis in the [4 + 2]-cycloaddition between 2-alkyl-3-formylheteroarenes and α,β-unsaturated aldehydes is described. Within the developed approach, the same aminocatalyst is employed for the independent activation of both starting materials, differentiating their properties via LUMO-lowering and HOMO-rising principles. By the combination of dearomative dienamine activation with iminium ion chemistry high enantio- and diastereoselectivity of th ...[more]

PMID: 35040652

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