1: With oxalyl dichloride in dichloromethane; N,N-dimethyl-formamide T=20°C; 2 h; 2: With tin(ll) chloride in dichloromethane; N,N-dimethyl-formamide T=0 - 5°C;

potassium carbonate in methanol; water 6 h; Reflux;

sulfuric acid; propionic acid anhydride in toluene T=-5 - 30°C; 3 h; Product distribution / selectivity;