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Photocatalytic sequential C-H functionalization expediting acetoxymalonylation of imidazo heterocycles.

ABSTRACT: The importance of functionalized imidazo heterocycles has often been featured in several impactful research both from academia and industry. Herein, we report a direct C-3 acetoxymalonylation of imidazo heterocycles using relay C-H functionalization enabled by organophotocatalysis starring zinc acetate in the triple role of an activator, ion scavenger as well as an acetylating reagent. The mechanistic investigation revealed a sequential sp² and sp³ C-H activation, followed by functionalization driven by zinc acetate coupled with the photocatalyst PTH. A variety of imidazo[1,2-a]pyridines and related heterocycles were explored as substrates along with several active methylene reagents, all generating the products with excellent yields and regioselectivity, thus confirming excellent functional group tolerability.

SUBMITTER: Singh D

PROVIDER: S-EPMC10186259 | biostudies-literature | 2023

REPOSITORIES: biostudies-literature

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Photocatalytic sequential C-H functionalization expediting acetoxymalonylation of imidazo heterocycles.

Singh Deepak D Pramanik Shyamal S Maity Soumitra S

Beilstein journal of organic chemistry 20230512

The importance of functionalized imidazo heterocycles has often been featured in several impactful research both from academia and industry. Herein, we report a direct C-3 acetoxymalonylation of imidazo heterocycles using relay C-H functionalization enabled by organophotocatalysis starring zinc acetate in the triple role of an activator, ion scavenger as well as an acetylating reagent. The mechanistic investigation revealed a sequential sp2 and sp3 C-H activation, followed ...[more]

PMID: 37205129

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