Katsuma Yuhei, Asakawa Hiroki, Yamashita Makoto
Department of Applied Chemistry , Faculty of Science and Engineering , Chuo University , 1-13-27 Kasuga , Bunkyo-ku , 112-8551 , Tokyo , Japan.
Department of Molecular and Macromolecular Chemistry , Graduate School of Engineering , Nagoya University , Furo-cho, Chikusa-ku , Nagoya , 464-8603 , Aichi , Japan . Email:
Chem Sci. 2017 Dec 11;9(5):1301-1310. doi: 10.1039/c7sc04759b. eCollection 2018 Feb 7.
The reaction of pinB-BMes (pin = pinacolato, Mes = 2,4,6-MeCH) with Xyl-NC (Xyl = 2,6-MeCH) and pyridine results in the formation of a pyridine-coordinated boraalkene that exhibits an intense color caused by an intramolecular charge-transfer interaction. In the presence of an excess of pyridine, the C-H bond of pyridine was selectively functionalized to afford a quinoid compound or an isocyanide-coupled product. Based on the concentration effect, the reaction stoichiometry, and previously reported DFT calculations, a reaction mechanism that involves several rearrangement reactions was proposed. Using the present method, substituted pyridines and N-heterocycles afforded the corresponding functionalized derivatives. A subsequent hydrolysis of one of the resulting products furnished an aminomethylated pyridine derivative in two steps from parent pyridine.
频哪醇硼酸酯-均三甲苯硼烷（pin = 频哪醇，Mes = 2,4,6-三甲基苯基）与2,6-二甲基苯基异腈（Xyl = 2,6-二甲基苯基）及吡啶反应，生成一种吡啶配位的硼烯烃，该硼烯烃因分子内电荷转移相互作用而呈现出强烈颜色。在过量吡啶存在下，吡啶的C-H键被选择性官能化，得到醌型化合物或异腈偶联产物。基于浓度效应、反应化学计量关系以及先前报道的密度泛函理论计算，提出了一种涉及多个重排反应的反应机理。采用本方法，取代吡啶和氮杂环可得到相应的官能化衍生物。所得产物之一随后经水解，从母体吡啶分两步得到氨基甲基化吡啶衍生物。
