An electrochemically induced C(sp³)–H amination of 2-aminobenzamides with ketones using TBAI as a catalyst was developed, and provided 2-benzoylquinazolin-4(3H)-ones under metal-free conditions. The reaction proceeded using the relatively low-toxicity methanol as the solvent, employed molecular oxygen as the ideal green oxidant in a simple undivided cell, and exhibited high atom economy. The mechanism of this C(sp³)–H amination strategy was concluded to involve generation of an acetophenone radical, and its easy further oxidation to form 2-oxo-2-phenylacetaldehyde.