Lanthanum Aryloxide/Pybox-Catalyzed Direct Asymmetric Mannich-Type Reactions Using a Trichloromethyl Ketone as a Propionate Equivalent Donor
作者:Hiroyuki Morimoto、Gang Lu、Naohiro Aoyama、Shigeki Matsunaga、Masakatsu Shibasaki
DOI:10.1021/ja073285p
日期:2007.8.1
Direct catalytic asymmetric Mannich-type reaction of a trichloromethyl ketone as a propionate equivalent donor is described. A new lanthanum aryloxide−iPr-pybox + lithium aryloxide combined catalyst was the most effective, promoting the reaction of N-2-thiophenesulfonyl imines with the trichloromethyl ketone. syn-Mannich adducts were obtained from various aryl, heteroaryl, alkenyl, and alkyl imines
描述了作为丙酸酯等效供体的三氯甲基酮的直接催化不对称曼尼希型反应。一种新的芳基氧化镧-iPr-pybox +芳基氧化锂组合催化剂是最有效的,促进了N-2-噻吩磺酰基亚胺与三氯甲基酮的反应。从各种芳基、杂芳基、烯基和烷基亚胺以 >99-72% 的产率、>30:1-8:1 的顺/反和 98-92% ee(来自丙酸酯等价供体)获得了 Syn-Mannich 加合物) 使用 2.5-10 mol% 催化剂。曼尼希加合物不仅转化为酯,而且转化为有用的结构单元。