1: 1-(tetrahydropyran-2-yloxy)-4-pentyne With n-butyllithium in tetrahydrofuran; hexane T=0°C; 0.25 h; 2: With N,N,N',N',N'',N''-hexamethylphosphoric triamide in tetrahydrofuran; hexane T=0°C; 0.25 h; 3: tridecyl iodide in tetrahydrofuran; N,N,N',N',N'',N''-hexamethylphosphoric triamide; hexane 20 h;

lithium in tetrahydrofuran; ammonia; dimethyl sulfoxide T=-60 - 20°C;

1.1: 95 percent / PPTS / CH2Cl2 / 15.5 h / 0 - 20 °C 2.1: n-BuLi / tetrahydrofuran; hexane / 0.25 h / 0 °C 2.2: 49 percent / tetrahydrofuran; hexane / 20 h View Scheme

1.1: 95 percent / PPTS / CH2Cl2 / 15.5 h / 0 - 20 °C 2.1: n-BuLi / tetrahydrofuran; hexane / 0.25 h / 0 °C 2.2: 49 percent / tetrahydrofuran; hexane / 20 h View Scheme