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Synthesis of Oxazinanones: Intramolecular Cyclization of Amino Acid-Derived Diazoketones via Silica-Supported HClO4 Catalysis.

ABSTRACT: A Brønsted acid catalyzed intramolecular cyclization of N-Cbz-protected diazoketones, derived from ?-amino acids, is described. The reaction proceeds under metal-free conditions and is promoted by ecofriendly silica-supported HClO4 as the catalyst and methanol as the solvent. This transformation enables the short synthesis of various 1,3-oxazinane-2,5-diones under mild reaction conditions and in good yields (up to 90%). The set-up is very simple; by just mixing all reagents together with no work-up necessary before purification, this protocol takes a greener approach.

SUBMITTER: Gallo RDC

PROVIDER: S-EPMC6376066 | biostudies-literature | 2019

REPOSITORIES: biostudies-literature

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Synthesis of Oxazinanones: Intramolecular Cyclization of Amino Acid-Derived Diazoketones via Silica-Supported HClO4 Catalysis.

Gallo Rafael D C RDC Campovilla Orlando C OC Ahmad Anees A Burtoloso Antonio C B ACB

Frontiers in chemistry 20190208

A Brønsted acid catalyzed intramolecular cyclization of N-Cbz-protected diazoketones, derived from α-amino acids, is described. The reaction proceeds under metal-free conditions and is promoted by ecofriendly silica-supported HClO4 as the catalyst and methanol as the solvent. This transformation enables the short synthesis of various 1,3-oxazinane-2,5-diones under mild reaction conditions and in good yields (up to 90%). The set-up is very simple; by just mixing all reagents tog ...[more]

PMID: 30800653

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