Preparation and Stille cross-coupling reaction of the first organotin reagents of azulenes. Easy access to poly(azulen-6-yl)benzene derivatives
作者:Shunji Ito、Tetsuo Okujima、Noboru Morita
DOI:10.1039/b203836f
日期:2002.8.8
afforded 1,4-di-, 1,3,5-tri-, 1,2,4,5-tetra-, 1,2,4-tri- and 1,2,3,5-tetra(azulen-6-yl)benzene derivatives (18, 20, 22, 24 and 25). The redox behavior of 18 and 22 was examined by cyclic voltammetry (CV) and compared with those of 20 and 24 reported previously. In contrast to the three-step reduction of 20, the compound 18 exhibited a reversible one-step two-electron reduction wave at −1.30 V upon CV,
第一种通用的有机金属试剂衍生自 天青石,即,6-(三- Ñ -butylstannyl)薁(1a)及其1,3-二乙氧羰基衍生物(1b),是由Pd(0)催化直接制备的。锡烷基化的与双6- bromoazulenes(三- Ñ -butyltin)。我们展示了该试剂在Stille交叉偶联反应中的实用性芳基, 酰基和a烯基卤化物以良好的收率得到6-芳基-,6-酰基-和双-azulenes。此外,该方法被应用于合成聚(azulen-6-基)苯衍生物。1b与1,4-二-,1,3,5-三-,1,2,4,5-四-和六溴苯的反应得到1,4-二-,1,3,5-三-, 1,2,4,5-四- ,1,2,4-三-和1,2,3,5-四(薁-6-基)苯衍生物(18,20,22,24和25)。18和22的氧化还原行为通过循环伏安法 (简历),并与之前报告的20和24进行比较。与20的三步还原相反,化合物18表现出可逆的一步两电子减少