Fe2O3 superparamagnetic nanoparticles emerged as a productive recyclable heterogeneous catalyst for the cyclization reaction between α‐keto acids and benzene‐1,2‐diamines to produce quinoxalinones as major products and benzimidazoles as minor products. The Fe2O3 nanoparticles displayed higher activity in the synthesis of quinoxalinones than a series of nano catalysts as well as iron‐, copper‐, nickel‐, and cobalt‐based homogeneous catalysts. Moreover, the Fe2O3 nanoparticles was easily recovered by magnetic decantation, and was reutilized without a remarkable deterioration in catalytic activity and selectivity towards quinoxalinones. To our best knowledge, this transformation was not previously conducted under heterogeneous catalysis conditions.

An efficient, one‐pot synthesis of 4‐substituted quinazoline derivatives via direct oxidative amination of C(sp3)–H bonds was demonstrated. The nature of the oxidant exhibited a considerable effect on the reaction, and tert‐butyl hydroperoxide in decane emerged as the best option. A variety of C1 sources could be used, affording 4‐substituted quinazolines in good yields. The three‐component reaction proceeded readily without any added catalyst, in which acetic acid from ammonium acetate was essential for the catalytic cycle. This protocol would offer a complementary pathway to previous methods in the synthesis of 4‐substituted quinazoline derivatives.