The Asymmetric Arylation Reaction. Encouraged by the initial results, we systematically studied the chiral aldehyde-catalyzed arylation reaction. Because of the excellent enantioselectivity of 3a obtained in Figure , chiral aldehyde CA-1 was chosen for optimization of the reaction conditions. Base screening indicated that inorganic bases were suitable for this reaction, and K3PO4 provided the greatest yield of 3a (Figure ). The choice of solvent also affected the yield of 3a. When this reaction was conducted in Et2O, product 3a was obtained in 86% yield with > 99% ee (Figure ). Then, the base equivalent and the reaction concentration were tuned. The results indicated that using 5 equivalents of K3PO4 and 0.2 M 2a (y = 1) produced the greatest yield (Figure ).