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Cascade aza-Wittig/6π-Electrocyclization in the Synthesis of 1,6-Dihydropyridines.

ABSTRACT: A metal-free protocol for the synthesis of substituted 1,6-dihydropyridines with quaternary stereogenic centers via a cascade aza-Wittig/6π-electrocyclization process has been developed. The high functional group compatibility and broad scope of this method were demonstrated by using a wide range of easily available vinyliminophosphoranes and ketones, with yields up to 97%. A modification of the obtained products allowed for an increase in complexity and chemical diversity. Finally, attempts for asymmetric synthesis of 1,6-dihydropyridines are demonstrated.

SUBMITTER: Polychronidou V

PROVIDER: S-EPMC8397428 | biostudies-literature | 2021 Aug

REPOSITORIES: biostudies-literature

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Cascade aza-Wittig/6π-Electrocyclization in the Synthesis of 1,6-Dihydropyridines.

Polychronidou Vasiliki V Krupp Anna A Strohmann Carsten C Antonchick Andrey P AP

Organic letters 20210722 15

A metal-free protocol for the synthesis of substituted 1,6-dihydropyridines with quaternary stereogenic centers via a cascade aza-Wittig/6π-electrocyclization process has been developed. The high functional group compatibility and broad scope of this method were demonstrated by using a wide range of easily available vinyliminophosphoranes and ketones, with yields up to 97%. A modification of the obtained products allowed for an increase in complexity and chemical diversity. Finally, attempts for ...[more]

PMID: 34291925

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