Highly Enantioselective Friedel−Crafts Reaction of Aromatic Amines with Ethyl Glyoxylate Catalyzed by Chiral Titanium(IV) Complexes: Practical Synthesis of Aminomandelic Acid Derivatives
作者:Yu Yuan、Xingwang Wang、Xin Li、Kuiling Ding
DOI:10.1021/jo034992d
日期:2004.1.1
The asymmetric Friedel−Crafts reaction of a variety of N,N-dialkylanilines with ethyl glyoxylate has been achieved by the catalysis of titanium complexes of BINOL derivatives to give corresponding ethyl esters of p-N,N-dialkylaminomandelic acids in high yields (85−99%) and good to excellent enantioselectivities (80−96.6% ee) under the optimized reaction conditions, which has added a new catalyst for
多种N,N-二烷基苯胺与乙醛酸乙酯的不对称Friedel-Crafts反应已通过BINOL衍生物的钛配合物催化以高产率得到相应的p - N,N-二烷基氨基扁桃酸乙酯而实现(85-在优化的反应条件下,其对映选择性(99%)和良好至优异的对映选择性(80-96.6%ee),为此类反应添加了新的催化剂。该反应还可以在以克为单位的减少的催化剂负载(1mol%)下进行,这提供了对映纯的氨基扁桃酸衍生物的实用合成。