tetrabutyl ammonium fluoride in tetrahydrofuran; water

1: 94 percent / imidazole / CH2Cl2 2: n-BuLi / hexane / 24 h / 0 - 20 °C 3: 4695 g / TBAF / tetrahydrofuran / 20 °C View Scheme

1: n-BuLi / hexane / 24 h / 0 - 20 °C 2: 4695 g / TBAF / tetrahydrofuran / 20 °C View Scheme

n-butyllithium Yield given. Multistep reaction;

1: (COCl)2; DMSO; Et3N / CH2Cl2 / -78 - 20 °C 2: 92 percent / EtMgBr / tetrahydrofuran; diethyl ether / 0 - 20 °C 3: 75 percent / PCC / CH2Cl2 / 15 h / 0 - 20 °C 4: BH3; Me2S; (R)-methyloxazaborolidine / toluene; tetrahydrofuran / 1 h / -30 °C 5: 92 percent / imidazole; 4-(dimethylamino)pyridine / dimethylformamide; CH2Cl2 / 15 h / 20 °C 6: CH2Cl2 / 2 h / 20 °C 7: H2; K2CO3 / Pd/C / ethanol / 20 °C / 4654.33 Torr 8: NaBH4; aq. NaOH / ethanol / 6 h / -10 °C 9: 2162 g / TsOH / methanol / 15 h / 0 - 20 °C 10: 80 percent / Ph2PH; n-BuLi / tetrahydrofuran; hexane / 20 h / Heating 11: 100 percent / K2CO3; tetrabutylammonium bromide / acetone / 8 h / Heating 12: 83 percent / aq. KOH / methanol / 3 h / Heating View Scheme

oxalyl dichloride; dimethyl sulfoxide; triethylamine in dichloromethane T=-78 - 20°C; Swern oxidation;