Metal‐Free Oxidative Coupling Reactions via σ‐Iodonium Intermediates: The Efficient Synthesis of Bithiophenes Using Hypervalent Iodine Reagents

The direct oxidative biaryl coupling reaction is an attractive tool for environmentally benign green chemistry. A novel direct method for the synthesis of bithiophene using a hypervalent iodine reagent has been developed. The reaction mechanism has also been investigated, casting light on the reaction intermediate and revealing the reactivity with iodonium salts.