1: 1) n-BuLi / 1) hexane, THF, -70 deg C, 15 min, 2) -40 deg C, 15 h 2: N(Et)3 / CH2Cl2 / 0.25 h / -5 °C 3: 71 percent / KOtBu / dimethylsulfoxide / 0.5 h / other 1,4-dihydroquinolinemesylates; conversion of 1,4-dihydroquinolines to 2-benzazepines View Scheme