Transition Metal-Free Catalyzed Oxidative Coupling of Anilines to Azo Compounds and Thiophenols to Disulfides

Introduction: Herein we report the efficient oxidative transformations of aryl amines to azoarenes and aryl thiols to the corresponding disulfides using diacetoxyiodobenzene and potassium iodide as transition metal-free catalysts in acetonitrile at room temperature. The developed protocols are highly efficient and employ readily accessible, inexpensive, and environmentally friendly starting. Methods: All the reactions were carried out in a fuming hood at room temperature (approximately 25- 30°C). The chemicals used in these reactions were purchased from Avra, Aldrich and Spectrochem with a minimum of 95-99% purities and used without further purification. Results: The reaction of DIB with KI would generate PhI(OAc)I through a partial AcO-I exchange process, and the subsequent reaction of 2PhI(OAc)I with aromatic amines should produce PhNI2 on the elimination of 2AcOH and 2PhI. Conclusion: The protocol was applicable to a wide range of aromatic amines and aromatic thiols under mild reaction conditions and has no safety concerns, requires inexpensive chemicals and is environmentally friendly.