Conversion of pyridine to imidazo[1,2-a]pyridines by copper-catalyzed aerobic dehydrogenative cyclization with oxime esters.

Conversion of pyridine to imidazo[1,2-a]pyridines by copper-catalyzed aerobic dehydrogenative cyclization with oxime esters.

Organic letters (2013-11-23)

Huawen Huang, Xiaochen Ji, Xiaodong Tang, Min Zhang, Xianwei Li, Huanfeng Jiang

ABSTRACT

A rapid and environmentally friendly conversion of pyridine to imidazo[1,2-a]pyridines has been developed via copper-catalyzed aerobic dehydrogenative cyclization with ketone oxime esters.

MATERIALS

Product Number

Brand

Product Description

326429

Sigma-Aldrich

Copper, wire, diam. 0.25 mm, 99.999% trace metals basis

61139

Sigma-Aldrich

Copper, turnings, purum p.a., ≥99.0%

326488

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Copper, beads, 2-8 mm, ≥99.99% trace metals basis

326410

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Copper, wire, diam. 0.64 mm, 99.995% trace metals basis

349216

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243086

Sigma-Aldrich

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Copper, foil, thickness 1.0 mm, 99.999% trace metals basis

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82800

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12816

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207780

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349224

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Copper, wire, diam. 2.0 mm, 99.999% trace metals basis

48305-U

Supelco

Pyridine solution, certified reference material, 2000 μg/mL in methanol

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Continuous cast copper (O), BCR^®, certified reference material, rod

275778

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307475

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326453

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311405

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774103

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Sigma-Aldrich

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