triethylamine in N,N-dimethyl-formamide T=60°C; 2 h;

1: 91 percent / CHCl3 / 22 h / Ambient temperature 2: 98.5 percent / conc. NH3 / 1.5 h / Ambient temperature 3: 50.9 percent / pyrophosphoryl chloride / 3 h / 40 °C 4: 41.4 percent / triethylamine / dimethylformamide / 2 h / 60 °C View Scheme

1: 50.9 percent / pyrophosphoryl chloride / 3 h / 40 °C 2: 41.4 percent / triethylamine / dimethylformamide / 2 h / 60 °C View Scheme

1: 98.5 percent / conc. NH3 / 1.5 h / Ambient temperature 2: 50.9 percent / pyrophosphoryl chloride / 3 h / 40 °C 3: 41.4 percent / triethylamine / dimethylformamide / 2 h / 60 °C View Scheme