After adding 3.19 g of 4-(5-methyl-[1,2,4]oxadiazol-3-yl)phenylamine, 10 g of MS3A, 1.56 g of Yb(OTf)3 and 4.84 ml of trimethylsilyl cyanide to a solution of 5.6 g of 4-methoxy-3-triisopropylsilanyloxybenzaldehyde [CAS No. 179260-96-6] in 98 ml of dichloromethane under a nitrogen atmosphere, the mixture was stirred at room temperature for 12 hours. The reaction mixture was filtered, and the filtrate was concentrated under reduced pressure. The residue was purified by silica gel column chromatography (ethyl acetate-heptane) to give a white solid (5.59 g).
