Asymmetric conjugate addition is an important synthetic methods for constructing new C-C bonds.1 Although transition-metal-catalyzed conjugate additions of boronic acids and their derivatives to a,p-unsaturated carbonyl compounds making use of Rh(Ⅰ),Ir(Ⅰ),Pd(Ⅰ)and Cu(Ⅰ)catalysts have been realized.transition-metal-free conjugate addition reactions are still an important alternative method due to their low toxicity,functional-group tolerance,operational simplicity,and high selectivity.2 In our work.we have developed an asymmetric conjugate addition of boronic acids to a,p-unsaturated ketones catalyzed by(S)-2,15-Br2-DHTP under mild reaction conditions(Fig.1).Enantioenriched products bearing a trifluoromethylated stereocenter were obtained in moderate to high yields and good to excellent enantioselectivities(up t0 99:1 er).In addition.heteroarylboronic acids were tolerated under this reaction condition,and gram-scale reactions were achieved without loss of enantioselectivities.3 Additional investigations to extend the scope to other substrates and applications of the resulting products are in progress.