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Palladium-Catalyzed Room Temperature Acylative Cross-Coupling of Activated Amides with Trialkylboranes.

ABSTRACT: A highly efficient acylative cross-coupling of trialkylboranes with activated amides has been effected at room temperature to give the corresponding alkyl ketones in good to excellent yields by using 1,3-bis(2,6-diisopropyl)phenylimidazolylidene and 3-chloropyridine co-supported palladium chloride, the PEPPSI catalyst, in the presence of K?CO? in methyl tert-butyl ether. The scope and limitations of the protocol were investigated, showing good tolerance of acyl, cyano, and ester functional groups in the amide counterpart while halo group competed via the classical Suzuki coupling. The trialkylboranes generated in situ by hydroboration of olefins with BH? or 9-BBN performed similarly to those separately prepared, making this protocol more practical.

SUBMITTER: Shi W

PROVIDER: S-EPMC6222728 | biostudies-literature | 2018 Sep

REPOSITORIES: biostudies-literature

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Palladium-Catalyzed Room Temperature Acylative Cross-Coupling of Activated Amides with Trialkylboranes.

Shi Weijia W Zou Gang G

Molecules (Basel, Switzerland) 20180920 10

A highly efficient acylative cross-coupling of trialkylboranes with activated amides has been effected at room temperature to give the corresponding alkyl ketones in good to excellent yields by using 1,3-bis(2,6-diisopropyl)phenylimidazolylidene and 3-chloropyridine co-supported palladium chloride, the PEPPSI catalyst, in the presence of K₂CO₃ in methyl <i>tert</i>-butyl ether. The scope and limitations of the protocol were investigated, showing good tolerance of acyl, cyano, and ester functiona ...[more]

PMID: 30241341

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