in N,N-dimethyl-formamide T=20°C;

ammonia in N,N-dimethyl-formamide 1 h;

naphthalene T=190 - 200°C; 3 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: 63.4 percent / ammonia / dimethylformamide / 1 h View Scheme

1: 98.5 percent / conc. NH3 / 1.5 h / Ambient temperature 2: 50.9 percent / pyrophosphoryl chloride / 3 h / 40 °C 3: 63.4 percent / ammonia / dimethylformamide / 1 h View Scheme

1: 50.9 percent / pyrophosphoryl chloride / 3 h / 40 °C 2: 63.4 percent / ammonia / dimethylformamide / 1 h View Scheme