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Microwave assisted regioselective halogenation of benzo[b][1,4]oxazin-2-ones via sp² C-H functionalization.

ABSTRACT: A microwave assisted, palladium-catalyzed regioselective halogenation of 3-phenyl-2H-benzo[b][1,4]oxazin-2-ones has been demonstrated using inexpensive and readily available N-halosuccinimide. The reaction utilizes the nitrogen atom present in the heterocyclic ring as the directing group to afford regioselective halogenated products in good to moderate yields. The established protocol provides wide substrate scope, high functional group tolerance, and high atom and step economy. The reaction proved to be cost-effective and time-saving as it required only a few minutes for completion and is amenable to gram scale. The halogen atoms present in synthesized products provide further scope for post-functionalization. Several post-functionalized products have also been synthesised to demonstrate the high utility of the reaction in the field of drug discovery and late-stage functionalization.

SUBMITTER: Kumar S

PROVIDER: S-EPMC9841512 | biostudies-literature | 2023 Jan

REPOSITORIES: biostudies-literature

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Microwave assisted regioselective halogenation of benzo[b][1,4]oxazin-2-ones via sp2 C-H functionalization.

Kumar Sandeep S Prince Gupta Mohit M Lalji Ram Sunil Kumar RSK Singh Brajendra K BK

RSC advances 20230116 4

A microwave assisted, palladium-catalyzed regioselective halogenation of 3-phenyl-2H-benzo[b][1,4]oxazin-2-ones has been demonstrated using inexpensive and readily available N-halosuccinimide. The reaction utilizes the nitrogen atom present in the heterocyclic ring as the directing group to afford regioselective halogenated products in good to moderate yields. The established protocol provides wide substrate scope, high functional group tolerance, and high atom and step econ ...[more]

PMID: 36741130

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