1.1: t-BuLi / pentane; diethyl ether / 0.5 h / -78 °C 1.2: [(n-Bu3P)CuI]4 / pentane; diethyl ether / 0.67 h / -10 °C 1.3: 80 percent / pentane; diethyl ether; tetrahydrofuran / 0.5 h / -60 °C 2.1: benzeneseleninic anhydride / tetrahydrofuran / 1 h / 20 °C 3.1: 515 mg / NaBH4 / ethanol / 7 h / -40 °C 4.1: p-TsOH; water / acetone / 12 h / 20 °C View Scheme