Granados Albert, Rivilla Iván, Cossío Fernando P, Vallribera Adelina
Department of Chemistry and Centro de Innovación en Química Avanzada (ORFEO-CINQA), Universitat Autònoma de Barcelona, 08193, Bellaterra (Cerdanyola del Vallès), Spain.
Departamento de Química Orgánica I and Centro de Innovación en Química Avanzada (ORFEO-CINQA), Universidad del País Vasco and Donostia International Physics Center (DIPC), P° Manuel Lardizabal, 3., 20018, Donostia-San Sebastián, Spain.
Chemistry. 2019 Jun 21;25(35):8214-8218. doi: 10.1002/chem.201900598. Epub 2019 May 6.
A highly enantioselective catalytic method for the synthesis of quaternary α-trifluoromethyl derivatives of 3-oxo esters is described. The reaction uses lanthanum(III) triflate and chiral PyBOX-type C -symmetric ligands to generate intermediate La complexes that incorporate an enolate moiety of the starting 3-oxo ester and the trifluoromethylation transfer reagent. The enantioselectivity of the reaction stems from the efficient blockage of one of the prochiral faces of the La enolate by one unit of the C -symmetric ligand.
描述了一种用于合成3-氧代酯的季α-三氟甲基衍生物的高度对映选择性催化方法。该反应使用三氟甲磺酸镧(III)和手性PyBOX型C对称配体生成中间镧配合物，该配合物包含起始3-氧代酯的烯醇负离子部分和三氟甲基化转移试剂。反应的对映选择性源于C对称配体的一个单元对镧烯醇负离子的一个前手性面的有效阻断。
