hydrogen; Lindlar's catalyst in ethanol P=760 Torr; 0.5 h;

1: 1) n-butyllithium / 1) HMPA, hexane, 0 deg C, 30 min, 2) 0 deg C, 4 h 2: 100 percent / diethyl ether / 4 h / Ambient temperature 3: 1) diisopropylamine, n-butyllithium / 1) THF, hexane, -78 deg C, 1 h, 2) -78 deg C, 20 min 4: 92 percent / H2 / 5percent Pd on CaCO3 / ethanol / 0.5 h / 760 Torr View Scheme

1: 100 percent / diethyl ether / 4 h / Ambient temperature 2: 1) diisopropylamine, n-butyllithium / 1) THF, hexane, -78 deg C, 1 h, 2) -78 deg C, 20 min 3: 92 percent / H2 / 5percent Pd on CaCO3 / ethanol / 0.5 h / 760 Torr View Scheme

1: 1) diisopropylamine, n-butyllithium / 1) THF, hexane, -78 deg C, 1 h, 2) -78 deg C, 20 min 2: 92 percent / H2 / 5percent Pd on CaCO3 / ethanol / 0.5 h / 760 Torr View Scheme

1: 1) n-butyllithium / 1) HMPA, hexane, 0 deg C, 30 min, 2) 0 deg C, 4 h 2: 100 percent / diethyl ether / 4 h / Ambient temperature 3: 1) diisopropylamine, n-butyllithium / 1) THF, hexane, -78 deg C, 1 h, 2) -78 deg C, 20 min 4: 92 percent / H2 / 5percent Pd on CaCO3 / ethanol / 0.5 h / 760 Torr View Scheme