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Decarboxylative borylation.

ABSTRACT: The widespread use of alkyl boronic acids and esters is frequently hampered by the challenges associated with their preparation. We describe a simple and practical method to rapidly access densely functionalized alkyl boronate esters from abundant carboxylic substituents. This broad-scope nickel-catalyzed reaction uses the same activating principle as amide bond formation to replace a carboxylic acid moiety with a boronate ester. Application to peptides allowed expedient preparations of ?-amino boronic acids, often with high stereoselectivity, thereby facilitating synthesis of the alkyl boronic acid drugs Velcade and Ninlaro as well as a boronic acid version of the iconic antibiotic vancomycin. The reaction also enabled the discovery and extensive biological characterization of potent human neutrophil elastase inhibitors, which offer reversible covalent binding properties.

SUBMITTER: Li C

PROVIDER: S-EPMC5807063 | biostudies-literature | 2017 Jun

REPOSITORIES: biostudies-literature

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Decarboxylative borylation.

Li Chao C Wang Jie J Barton Lisa M LM Yu Shan S Tian Maoqun M Peters David S DS Kumar Manoj M Yu Antony W AW Johnson Kristen A KA Chatterjee Arnab K AK Yan Ming M Baran Phil S PS

Science (New York, N.Y.) 20170413 6342

The widespread use of alkyl boronic acids and esters is frequently hampered by the challenges associated with their preparation. We describe a simple and practical method to rapidly access densely functionalized alkyl boronate esters from abundant carboxylic substituents. This broad-scope nickel-catalyzed reaction uses the same activating principle as amide bond formation to replace a carboxylic acid moiety with a boronate ester. Application to peptides allowed expedient preparations of α-amino ...[more]

PMID: 28408721

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