New type chiral 1,1'-bi-2-naphthol monoester (BIMES) ligands were easily prepared from chiral 1,1'-bi-2-naphthol (BINOL) by the reaction with corresponding acid chlorides in the presence of triethylamine and 4-dimethylaminopyridine in good yields (77-86%). Their structures were characterized by means of infrared and 1{sup left}H NMR analyses. Asymmetric conjugate addition of alkylmetal reagent to enone was examined. We found that the conjugate addition of diethylzinc to chalcone was performed in the presence of the copper complex, which was prepared from chiral sodium 1,1'-bi-2-naphthol monoester (BIMES-Na) and copper(I) iodide, to give the product in 63% yield with high enantioselectivity (93% ee). This result shows that the formation of copper catalyst is most important for getting good yield and high enantiomeric excess. The enantioselective addition of diethylzinc to aryl aldehydes proceeded smoothly to give secondary aryl alcohols in good yield with moderate enantioselectity (up to 48% ee). The BIMES ligands possess an excellent environment for the asymmetric catalysis, and it is expected to develop new asymmetric reactions using BIMES ligands.
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