1: 92 percent / 220 °C 2: 91 percent / 10percent aq. KOH / methanol / 14 h / Ambient temperature View Scheme

sodium azide in N,N-dimethyl-formamide T=150°C; 5 h;

trimethylsilylazide; N,N-diethyl carbamoyl chloride in acetonitrile 18 h; Heating;

1: 65 percent / m-chloroperbenzoic acid (87percent) / 1,2-dichloro-ethane / 3 h / 65 °C 2: 85 percent / trimethylsilyl azide, diethylcarbamoyl chloride / acetonitrile / 18 h / Heating View Scheme

T=220°C;