sodium azide in N,N,N',N',N'',N''-hexamethylphosphoric triamide T=0 - 20°C; Inert atmosphere;

pyridinium chlorochromate in dichloromethane 1.5 h; Ambient temperature;

1: 1.) aq. HCl, NaNO2, 2.) NaN3 / 1.) 0 deg C, 1h, 2.) from 5 deg C to RT 2: 91 percent / pyridinium chlorochromate / CH2Cl2 / 1.5 h / Ambient temperature View Scheme