N-bromosuccinmide; 2,2'-azo-bisisobutyronitrile in tetrachloromethane; chloroform T=65°C; 15 h;

1: 99 percent / K2CO3 / methanol / 0.03 h / Ambient temperature 2: 46 percent / NBS / AIBN / CHCl3; CCl4 / 15 h / 65 °C View Scheme

1: 1) LDA / 1) THF, hexanes, -78 deg C, 2) -19 to -15 deg C 2: 79 percent / NaBH4 / tetrahydrofuran; propan-2-ol / a) 0 deg C to room temperature, overnight, b) 0 deg C to room temperature, 8 h 3: 84.5 percent / methanesulfonic acid / toluene / 0.33 h / Heating View Scheme

1: 1) LDA, 2) LiOMe / 1) THF, -78 deg C, 1 h, 2) THF, -5 deg C 2: 99 percent / trifluoroacetic acid / 24 h / Heating 3: 1) LDA / 1) THF, hexanes, -78 deg C, 2) THF, -20 to -15 deg C View Scheme

1: 1) LDA, 2) LiOMe / 1) THF, -78 deg C, 1 h, 2) THF, -5 deg C 2: 99 percent / trifluoroacetic acid / 24 h / Heating 3: 1) LDA / 1) THF, hexanes, -78 deg C, 2) THF, -6 to -1 deg C, 15 min 4: methanesulfonic acid / toluene / 0.33 h / Heating View Scheme

1: 93 percent / W-2 Raney Nickel / tetrahydrofuran / 1.) 0 deg C to room temp., 2.) room temp., 30 min 2: 85 percent / NBS / CCl4 / 120 h View Scheme

1: 1) LDA / 1) THF, hexanes, -78 deg C, 2) -19 to -15 deg C 2: 79 percent / NaBH4 / tetrahydrofuran; propan-2-ol / a) 0 deg C to room temperature, overnight, b) 0 deg C to room temperature, 8 h View Scheme

1: 1) LDA / 1) THF, hexanes, -78 deg C, 2) -19 to -15 deg C 2: 100 percent / NaBH4 / ethanol; tetrahydrofuran / 0 deg C to room temperature, overnight View Scheme