sodium hydride in tetrahydrofuran; N,N,N',N',N'',N''-hexamethylphosphoric triamide Ambient temperature;

1: 55 percent / 1,2-dimethoxy-ethane / 2 h / 85 °C 2: 92 percent / NaH / tetrahydrofuran; hexamethylphosphoric acid triamide / Ambient temperature View Scheme