Reactions of 2-aminobenzamides with diaryliodonium salts in N,N-dimethylacetamide (DMA) led to the formation of unexpected product quinazoline-4(3H)-one derivatives instead of the desired N-arylated 2-aminobenzamides. Most likely the diaryliodonium salts activated the sp3 C-H of N-methyl group of DMA through oxidation thereby produced an iminium species, the reaction of which with 2-aminobenzamides caused the annulation. © 2021 The Author(s)