Chiral propargylic alcohols are versatile synthons in organic chemistry, and catalytic asymmetric alkynylzinc addition to aldehydes can provide various chiral propargylic alcohols with high enantioselectivity . As shown in Table , Ti(O-i-Pr)4-catalyzed addition of phenylacetylene (24a) to benzaldehyde (22a) was selected as the model reaction to test our ligands and (R)-BINOL in the presence of ZnMe2 using dry dichloromethane (DCM) as the solvent at 0 o C (entries 1-12)), and (S)-L5 provided higher yield (85%) and highest ee value (93% ee) (entry 5). Other solvents, toluene, diethyl ether and THF, were attempted (entries 13-15), and they were inferior to DCM (entry 5). Subsequently, we surveyed substrate scope on the enantioselective addition of alkynes (25) to aldehydes (22). As shown in Fig. , most of the tested aldehydes (22) and alkynes (25) afforded high yields and good to excellent ee values. During our screening, we found that addition of phenylacetylene (24a) to 3-bromobenzaldehyde only afforded 74% ee with (S)-L5 as the ligand. known, determined or assigned by analogy (see Supplementary Information), and ee values determined by HPLC analysis using a chiral stationary phase (see Supplementary Information).