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Direct Access to Highly Functionalized Heterocycles through the Condensation of Cyclic Imines and ?-Oxoesters.

ABSTRACT: A facile, gram-scale preparation of 2-hydroxy-5,6,7,7a-tetrahydro-3H-pyrrolizin-3-ones and 2-hydroxy-6,7,8,8a-tetrahydroindolizin-3(5H)-ones from a condensation cyclization of ?-oxoesters with five- and six-membered cyclic imines, respectively, is reported. This transformation enables a concise, three-step synthesis of the natural products phenopyrrozin and p-hydroxyphenopyrrozin. Further, biologically relevant scaffolds, such as ?-quaternary ?-homo prolines and ?-lactams, are also prepared in two- to three-steps from the versatile 2-hydroxy-5,6,7,7a-tetrahydro-3H-pyrrolizin-3-one core.

SUBMITTER: Cusumano AQ

PROVIDER: S-EPMC6008790 | biostudies-literature | 2017 Dec

REPOSITORIES: biostudies-literature

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Direct Access to Highly Functionalized Heterocycles through the Condensation of Cyclic Imines and α-Oxoesters.

Cusumano Alexander Q AQ Boudreau Matthew W MW Pierce Joshua G JG

The Journal of organic chemistry 20171205 24

A facile, gram-scale preparation of 2-hydroxy-5,6,7,7a-tetrahydro-3H-pyrrolizin-3-ones and 2-hydroxy-6,7,8,8a-tetrahydroindolizin-3(5H)-ones from a condensation cyclization of α-oxoesters with five- and six-membered cyclic imines, respectively, is reported. This transformation enables a concise, three-step synthesis of the natural products phenopyrrozin and p-hydroxyphenopyrrozin. Further, biologically relevant scaffolds, such as α-quaternary β-homo prolines and β-lactams, are also prepared in t ...[more]

PMID: 29206454

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