title: Highly enantioselective Friedel-Crafts reaction of aromatic amines with ethyl glyoxylate catalyzed by chiral titanium(IV) complexes: practical synthesis of aminomandelic acid derivatives.
abstract: 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 this class of reactions. The reaction could also be carried out at a reduced catalyst loading (1 mol %) in gram scale, which provided a practical synthesis of enantiopure aminomandelic acid derivatives.
authors.affiliation: State Key Laboratory of Organometallic Chemistry, Shanghai Institute of Organic Chemistry, Chinese Academy of Sciences, 354 Fenglin Road, Shanghai 200032, P. R. China.
authors.forename: Yu
authors.initials: Y
authors.lastname: Yuan
authors.forename: Xingwang
authors.initials: X
authors.lastname: Wang
authors.forename: Xin
authors.initials: X
authors.lastname: Li
authors.forename: Kuiling
authors.initials: K
authors.lastname: Ding