1: 92 percent / NaNH2 / tetrahydrofuran; hexamethylphosphoric acid triamide / 1.) -78 degC 2.) 50 degC, 2 h 2: 94 percent / P(C6H5)3*Br2, collidine / CH2Cl2 / 5 h / Ambient temperature View Scheme

1: 92 percent / NaNH2 / tetrahydrofuran; hexamethylphosphoric acid triamide / 1.) -78 degC 2.) 50 degC, 2 h 2: 94 percent / P(C6H5)3*Br2, collidine / CH2Cl2 / 5 h / Ambient temperature 3: 1.) n-butyllithium, HMPA / 1.)THF, hexane, -78 degC to 0 degC 2.) 45-50 degC, 2 h 4: 63 percent / 5percent HCl / tetrahydrofuran; H2O / 2 h / 50 °C View Scheme

sodium amide in tetrahydrofuran; N,N,N',N',N'',N''-hexamethylphosphoric triamide 1.) -78 degC 2.) 50 degC, 2 h;

1: 92 percent / NaNH2 / tetrahydrofuran; hexamethylphosphoric acid triamide / 1.) -78 degC 2.) 50 degC, 2 h View Scheme

1: 92 percent / NaNH2 / tetrahydrofuran; hexamethylphosphoric acid triamide / 1.) -78 degC 2.) 50 degC, 2 h 3: 72 percent / P(C6H5)3, CBr4 / diethyl ether / 4 h View Scheme

1: 92 percent / NaNH2 / tetrahydrofuran; hexamethylphosphoric acid triamide / 1.) -78 degC 2.) 50 degC, 2 h 3: 81 percent / PCl5, pyridine / CH2Cl2 / 2 h View Scheme