Cyanocuprates Convert Carboxylic Acids Directly into Ketones
Douglas T Genna and Gary H. Posner
*Department of Chemistry, School of Arts and Sciences, The Johns Hopkins University, 3400 North Charles Street, Baltimore, Maryland 21218-2685, United States, Email: ghpjhu.edu
D. T Genna, G. H. Posner, Org. Lett., 2011, 13, 5358-5361.
DOI: 10.1021/ol202237j (free Supporting Information)
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Carboxylic acids were converted directly in good yields into ketones using excess alkyl cyanocuprates (R2CuLi•LiCN). A substrate with a stereocenter α to the carboxylic acid was converted with very little loss of enantiomeric purity. A variety of functional groups were tolerated including aryl bromides. This direct transformation involves a relatively stable copper ketal tetrahedral intermediate.
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