in toluene Addition; 120 h; Heating;

1: 1) n-BuLi / 1) THF, hexane, 5 deg C, 2) THF 2: 72 percent / H2 / 5percent Pd/C / ethyl acetate / 2068.6 Torr View Scheme

n-butyllithium in tetrahydrofuran; hexane; 1-chloro-1,1-difluoro-methane

1.1: n-BuLi / tetrahydrofuran; hexane / 0.17 h / 0 °C 1.2: 58 percent / tetrahydrofuran; hexane / -78 - 20 °C 2.1: 87 percent / tetrabutylammonium fluoride / tetrahydrofuran / 0 - 20 °C 3.1: 51 percent / Ph2S2 / cyclohexane; dioxane / 3 h / Photolysis 4.1: 78 percent / PDC / dimethylformamide / 3 h / 40 - 50 °C 5.1: 79 percent / DCC; HOBt / CH2Cl2 / 20 °C 6.1: 79 percent / p-toluenesulfonic acid / CH2Cl2 / 1 h / 20 °C 7.1: 69 percent / BF3*Et2O / various solvent(s) / 1 h / 20 °C View Scheme

sodium hexamethyldisilazane in tetrahydrofuran T=-75°C;