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Direct synthesis of amides from carboxylic acids and amines using B(OCH2CF3)3.

ABSTRACT: B(OCH2CF3)3, prepared from readily available B2O3 and 2,2,2-trifluoroethanol, is as an effective reagent for the direct amidation of a variety of carboxylic acids with a broad range of amines. In most cases, the amide products can be purified by a simple filtration procedure using commercially available resins, with no need for aqueous workup or chromatography. The amidation of N-protected amino acids with both primary and secondary amines proceeds effectively, with very low levels of racemization. B(OCH2CF3)3 can also be used for the formylation of a range of amines in good to excellent yield, via transamidation of dimethylformamide.

SUBMITTER: Lanigan RM

PROVIDER: S-EPMC3671500 | biostudies-literature | 2013 May

REPOSITORIES: biostudies-literature

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Direct synthesis of amides from carboxylic acids and amines using B(OCH2CF3)3.

Lanigan Rachel M RM Starkov Pavel P Sheppard Tom D TD

The Journal of organic chemistry 20130416 9

B(OCH2CF3)3, prepared from readily available B2O3 and 2,2,2-trifluoroethanol, is as an effective reagent for the direct amidation of a variety of carboxylic acids with a broad range of amines. In most cases, the amide products can be purified by a simple filtration procedure using commercially available resins, with no need for aqueous workup or chromatography. The amidation of N-protected amino acids with both primary and secondary amines proceeds effectively, with very low levels of racemizati ...[more]

PMID: 23586467

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