Peroxides as “Switches” of Dialkyl <i>H</i>-Phosphonate: Two Mild and Metal-Free Methods for Preparation of 2-Acylbenzothiazoles and Dialkyl Benzothiazol-2-ylphosphonates
作者:Xiao-Lan Chen、Xu Li、Ling-Bo Qu、Yu-Chun Tang、Wen-Peng Mai、Dong-Hui Wei、Wen-Zhu Bi、Li-Kun Duan、Kai Sun、Jian-Yu Chen、Dian-Dian Ke、Yu-Fen Zhao
DOI:10.1021/jo501791n
日期:2014.9.5
Two mild and metal-free methods for the preparation of two kinds of important benzothiazole derivatives, 2-acylbenzothiazoles and dialkyl benzothiazol-2-ylphosphonates, respectively, were developed. The diallcyl H-phosphonate (RO)(2)P(O)H exists in equilibrium with its tautomer dialkyl phosphite (RO)(2)POH. TBHP triggered alpha-carbon-centered phosphite radical formation, whereas DTBP triggered phosphorus-centered phosphonate radical formation. The two types of radicals led respectively to two different reaction processes, the direct C-2-acylation of benzothiazoles and C-2-phosphonation of benzothiazoles.