Enantioselective α-hydroxylation of β-keto esters catalyzed by chiral S-timolol derivatives
作者:Yuanchun Cai、Mingming Lian、Zhi Li、Qingwei Meng
DOI:10.1016/j.tet.2012.07.003
日期:2012.9
derived from the β-blocker inhibitor S-timolol determined the most active catalyst of asymmetric α-hydroxylation of β-keto esters. (R)-1-(tert-butylamino)-3-(3,4,5-trimethoxyphenoxy) propan-2-ol (3k) was the most effective derivative, enantioselectively catalyzing α-hydroxylation of β-keto esters using tert-butyl hydroperoxide as the oxidant in hexane to afford the corresponding products in excellent yield
由β-阻滞剂抑制剂S-噻吗洛尔衍生的芳氧基氨基丙醇有机催化剂的筛选确定了β-酮酯的不对称α-羟基化的最具活性的催化剂。(R)-1-(叔丁基氨基)-3-(3,4,5-三甲氧基苯氧基)丙烷-2-醇(3k)是最有效的衍生物,它使用叔-对映体催化β-酮酸酯的α-羟基化。丁基过氧化氢作为己烷中的氧化剂,以优异的收率和良好的对映选择性(高达96%的收率,88%ee)提供相应的产物。