A novel, metal catalyst-free, and efficient method has been developed for the synthesis of (pyrazol-4-ylidene)pyridine derivatives. The process involves dehydrogenative coupling of 1-amino-2-imino-pyridines with 1-aryl-5-pyrazolone derivatives utilizing O as the sole oxidant. The new method benefits from a high atom economy, efficiency, and substrate scope, as well as the simplicity of reaction and product purification procedures.