Phosphorus(V) oxychloride (POCl3) is a chlorinating agent that reacts with dimethylformamide (DMF) to form Vilsmeier reagent for Vilsmeier-Haack formylation reactions. It can also be used as a reagent in the synthesis of:
Quinazolin-4(3H)-one derivatives from 2-aminobenzamides via in situ preparation of Vilsmeier reagent.
Substituted 1-arylseleno-4-halo-2-enes by treating conjugated dienes with arylselenenamides.
3-methylthioimidazo[1,2-a]pyridines and imidazo-fused heterocycles in the presence of DMSO.