1: 95 percent / CH3CO2NH4 / acetic acid / 0.17 h / Ambient temperature 2: 99 percent / pyridinium hydrobromide perbromide / ethanol / 0.17 h / Ambient temperature 3: 86 percent / 1M BBr3 / CH2Cl2 / 12 h / -20 °C View Scheme

Multi-step reaction with 2 steps 1: glacial acetic acid, conc. HCl / H2O / 72 h / Ambient temperature2: glacial acetic acid, conc. HCl / H2O / 72 h / Ambient temperature  

Multi-step reaction with 2 steps 1: 61 percent / pyridinium dichromate / dimethylformamide / 9 h / Ambient temperature2: 1.) glacial acetic acid, conc. HCl; 2.) glacial acetic acid, conc. HCl / 1.) water, 3 d, RT; 2.) water, 3 d, RT  

With  hydrogenchloride; acetic acid  1.) water, 3 d, RT; 2.) water, 3 d, RT;  Yield given. Multistep reaction;