Graduate School of Pharmaceutical Sciences, The University of Tokyo, 7-3-1 Hongo, Bunkyo-ku, Tokyo 113-0033, Japan .
Molecules. 2010 Jan 22;15(1):532-44. doi: 10.3390/molecules15010532.
Catalytic asymmetric 1,4-addition of beta-keto esters to nitroalkenes is described. 2.5 mol % of a homobimetallic Lewis acid/Brønsted base bifunctional Co2-Schiff base complex smoothly promoted the reaction in excellent yield (up to 99%), diastereoselectivity, and enantioselectivity (up to >30:1 dr and 98% ee). Catalyst loading was successfully reduced to 0.1 mol %. Mechanistic studies suggested that intramolecular cooperative functions of the two Co-metal centers are important for high catalytic activity and stereoselectivity.
描述了β-酮酯对硝基烯烃的催化不对称 1,4-加成反应。2.5 摩尔%的同双金属路易斯酸/布朗斯特碱双功能 Co2-Schiff 碱配合物能以优异的收率（高达 99%）、非对映选择性和对映选择性（高达>30:1 dr 和 98%ee）顺利地促进反应。催化剂的用量成功地降低到 0.1 摩尔%。机理研究表明，两个 Co 金属中心的分子内协同作用对于高催化活性和立体选择性是很重要的。
