Enhanced Rate and Selectivity by Carboxylate Salt as a Basic Cocatalyst in Chiral N-Heterocyclic Carbene-Catalyzed Asymmetric Acylation of Secondary Alcohols
| Autor: | Kiyosei Takasu, Shingo Harada, Satoru Kuwano, Ken-ichi Yamada, Raphaël Oriez, Bubwoong Kang, Yousuke Yamaoka |
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| Rok vydání: | 2013 |
| Předmět: |
chemistry.chemical_classification
Acylation Carboxylic Acids Salt (chemistry) Stereoisomerism General Chemistry Biochemistry Medicinal chemistry Desymmetrization Catalysis Kinetic resolution chemistry.chemical_compound Colloid and Surface Chemistry chemistry Alcohols Organic chemistry Salts Carboxylate Amines Selectivity Methane Carbene |
| Zdroj: | Journal of the American Chemical Society. 135:11485-11488 |
| ISSN: | 1520-5126 0002-7863 |
| DOI: | 10.1021/ja4055838 |
| Popis: | The rate and enantioselectivity of chiral NHC-catalyzed asymmetric acylation of alcohols with an adjacent H-bond donor functionality are remarkably enhanced in the presence of a carboxylate cocatalyst. The degree of the enhancement is correlated with the basicity of the carboxylate. With a cocatalyst and a newly developed electron-deficient chiral NHC, kinetic resolution and desymmetrization of cyclic diols and amino alcohols were achieved with extremely high selectivity (up to s = 218 and 99% ee, respectively) at a low catalyst loading (0.5 mol %). This asymmetric acylation is characterized by a unique preference for alcohols over amines, which are not converted into amides under the reaction conditions. |
| Databáze: | OpenAIRE |
| Externí odkaz: |
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