1: 91 percent / lithium diisopropylamide / tetrahydrofuran / 1 h / Ambient temperature 2: 1.) n-butyllithium / 1.)THF, hexane, -78 degC 2.) room temperature, overnight 3: 80 percent / triphenylphosphine dibromide, collidine / CH2Cl2 / 5 h / Ambient temperature View Scheme