The highly efficient synthesis of benzoxazole, benzothiazole and benzimidazole has attracted much attention due to their superior biological activities. However, developing environmentally friendly and poisoning-resistant catalysts in heterogeneous catalytic systems remains a critical challenge. Herein, an atomically dispersed Co₁/NC catalyst was fabricated by facile pyrolysis of a zeolitic imidazolate framework (ZnCo-ZIF). The Co₁/NC catalyst exhibited excellent oxidation catalysis, sulfur-resistance and reusability performance. The mass specific activity (MSA) of Co₁/NC was up to 42.0 mol_2-PBO mol_Co⁻¹ h⁻¹, much higher than that of the Co/NC nano-catalyst (15.6 mol_2-PBO mol_Co⁻¹ h⁻¹). Mechanism studies showed that O₂ was activated by atomically dispersed Co active species to form ¹O₂ and ˙O₂⁻, which were responsible for the dehydrogenation of the key imine intermediates to produce 2-phenylbenzoxazole (2-PBO). The current work represents a novel feasible strategy for the synthesis of bioactive heterocyclic compounds using efficient, stable and green heterogeneous catalysts.