Metal-free direct C–H functionalization reactions are a promising approach to convert hydrocarbon feedstock into value-added molecules. Diacetoxyl iodobenzene (DIB) is a benchtop stable hypervalent iodine compound that is frequently used as a non-metal oxidant in C–H functionalization. However, DIB has a relatively low reactivity and an acid promoter is usually required to achieve satisfactory performance
Metal-Free Regioselective Oxidative Biaryl Coupling Leading to Head-to-Tail Bithiophenes: Reactivity Switching, a Concept Based on the Iodonium(III) Intermediate
作者:Koji Morimoto、Nobutaka Yamaoka、Chieko Ogawa、Tomofumi Nakae、Hiromichi Fujioka、Toshifumi Dohi、Yasuyuki Kita
DOI:10.1021/ol101498r
日期:2010.9.3
A new synthetic concept for obtaining unsymmetrical biaryl coupling products by an oxidative method is reported. Our synthetic strategy casts light on the reaction intermediate for switching the reactivity of 3-substituted thiophenes. On the basis of this strategy, a novel direct method for the synthesis of head-to-tail bithiophenes using hypervalent iodine(III) reagents has been developed.