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Base Mediated Tandem Vinylogous Addition and Cyclization of ?-Phosphonyl/Sulfonyl Crotonates and Ynones: Synthesis of Functionalized 2-Pyrones.

ABSTRACT: A general method for highly functionalized 2-pyrones via a base-mediated sequential vinylogous addition and cyclization of ?-phosphonyl/sulfonyl crotonates and ynones are described. An exclusive E-geometry with respect to the newly generated olefin substituent at C3 of pyrone was observed. Imino glyoxalates and glycine imines similarly reacted with ynones to deliver 3-imino pyrones.

SUBMITTER: Parameshwar M

PROVIDER: S-EPMC6854826 | biostudies-literature | 2019 Nov

REPOSITORIES: biostudies-literature

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Base Mediated Tandem Vinylogous Addition and Cyclization of γ-Phosphonyl/Sulfonyl Crotonates and Ynones: Synthesis of Functionalized 2-Pyrones.

Parameshwar Matam M Rajesh Manda M Balasubramanian Sridhar S Sridhar Reddy Maddi M

ACS omega 20191030 20

A general method for highly functionalized 2-pyrones via a base-mediated sequential vinylogous addition and cyclization of γ-phosphonyl/sulfonyl crotonates and ynones are described. An exclusive E-geometry with respect to the newly generated olefin substituent at C3 of pyrone was observed. Imino glyoxalates and glycine imines similarly reacted with ynones to deliver 3-imino pyrones. ...[more]

PMID: 31737846

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