1: With triphenylphosphine in tetrahydrofuran T=0 - 20°C; 16 h; 2: With ammonium hydroxide in tetrahydrofuran 3 h; 3: With hydrogenchloride; sodium hydroxide more than 3 stages;

1: With diphenyl phosphoryl azide; 1,8-diazabicyclo[5.4.0]undec-7-ene in toluene T=20°C; 16 h; 2: With hydrogenchloride in diethyl ether; water; toluene

sodium azide in N,N-dimethyl-formamide T=95°C;

sodium azide in N,N-dimethyl-formamide T=20°C; 2 h;

1.1: PPh3 / tetrahydrofuran / 16 h / 20 °C 1.2: aq. NH3 / 3 h 1.3: aq. NaOH / 1 h 2.1: 1.46 g / Et3N / tetrahydrofuran / 2 h / 20 °C 3.1: 88 percent / CuI; iPr2NH / PdCl2(PPh3)2 / 5 h / 20 °C 4.1: 45 percent / TBAF / tetrahydrofuran; dimethylformamide / 12 h / Heating View Scheme

1.1: PPh3 / tetrahydrofuran / 16 h / 20 °C 1.2: aq. NH3 / 3 h 1.3: aq. NaOH / 1 h 2.1: pyridine / 2 h / 20 °C View Scheme