文献类型：期刊文献

英文题名：An Air-Stable Organoboron Compound, Dithienooxadiborepine: Preparation and Functionalization

作者：Yan, Qifan[1];Yin, Mengxuan[1];Chen, Cheng[1];Zhang, Yuankun[1]

机构：[1]East China Univ Sci & Technol, Sch Chem & Mol Engn, Key Lab Adv Mat, Shanghai 200237, Peoples R China

年份：2018

卷号：83

期号：16

起止页码：9096

外文期刊名：JOURNAL OF ORGANIC CHEMISTRY

收录：;EI(收录号：20182705400554);WOS:【SCI-EXPANDED(收录号:WOS:000442451500024)】；

基金：This work was financially supported by the National Natural Science Foundation of China (21602061) and the Fundamental Research Funds for the Central Universities (WJ1714009). We thank Mr. Jiajun Xie of Peking University for DFT calculations.

语种：英文

外文关键词：Molecules - Chemical bonds - Organic polymers - Single crystals

摘要：pi-Conjugated organoboron molecules, which are easy to prepare, stable against moisture, and easy to functionalize, are scarce. Here, we report a one-pot synthesis of an air-stable organoboron compound, dithienooxadiborepine 1 in 17% yield on a 600 mg scale without separation or handling an air-sensitive intermediate. Dithienooxadiborepine 1 showed excellent stability under ambient conditions, allowing conventional column chromatography purification. Functionalization of 1 was realized via direct bromination using NBS and further Stille coupling reactions, giving access to longer pi-conjugated molecules SA and SB. Single-crystal structures of compounds 4, 5A, and 5B not only unambiguously verified the chemical identity of dithienooxadiborepine 1 but also revealed that both the seven-member oxadiborepine ring and the 5-7-5 fused dithienooxadiborepine ring system are planar. UV-vis absorption and fluorescence emission measurements of SA and 5B showed bathochromic shifted absorption and emission relative to 1, evidencing good pi-conjugation. Cyclic voltammograms of SA and SB displayed two reduction peaks corresponding to two electron-accepting events at two boron atoms. These results proved dithienooxadiborepine 1 a potent pi-conjugating building block for electron-accepting materials.