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Intercepted-Knoevenagel condensation for the synthesis of unsymmetrical fused-tricyclic 4H-pyrans.

ABSTRACT: 4H-Pyrans (4H-Pys) and 1,4-dihydropyridines (1,4-DHPs) are important classes of heterocyclic scaffolds in medicinal chemistry. Herein, an indium(III)-catalyzed one-pot domino reaction for the synthesis of highly functionalized 4H-Pys, and a model of 1,4-DHP is reported. This alternative approach to the challenging Hantzsch 4-component reaction enables the synthesis of fused-tricyclic heterocycles, and the mechanistic studies underline the importance of an intercepted-Knoevenagel adduct to achieve higher chemoselectivity towards these types of unsymmetrical heterocycles.

SUBMITTER: Shearer C

PROVIDER: S-EPMC6859900 | biostudies-literature | 2019 Oct

REPOSITORIES: biostudies-literature

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Intercepted-Knoevenagel condensation for the synthesis of unsymmetrical fused-tricyclic 4H-pyrans.

Shearer Charles C Desaunay Oriane O Zorc Stephen S Richaud Alexis D AD Samanta Shyam S SS Jeedimalla Nagalakshmi N Roche Stéphane P SP

Tetrahedron 20190917 43

4H-Pyrans (4H-Pys) and 1,4-dihydropyridines (1,4-DHPs) are important classes of heterocyclic scaffolds in medicinal chemistry. Herein, an indium(III)-catalyzed one-pot domino reaction for the synthesis of highly functionalized 4H-Pys, and a model of 1,4-DHP is reported. This alternative approach to the challenging Hantzsch 4-component reaction enables the synthesis of fused-tricyclic heterocycles, and the mechanistic studies underline the importance of an intercepted-Knoeven ...[more]

PMID: 31741543

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