环八[1,2-b:4,3-b′:5,6-b″:8,7-b′″]四噻吩的高效合成及其反应机理分析  

Studies on the Efficient Synthesis of Cycloocta[1,2-b:4,3-b′:5,6-b″:8,7-b′″]Tetrathiophene and Its Reaction Mechanism

作　　者：李路[1] 王鹏飞[1] 李春丽[1] 王华[1] 

机构地区：[1]河南大学纳米材料工程研究中心,河南开封475004

出　　处：《河南大学学报（自然科学版）》2017年第2期202-207,共6页Journal of Henan University:Natural Science

基　　金：国家自然科学基金资助项目(21270255)

摘　　要：以2,2′-二溴-5,5′-二(三甲基硅基)-3,3′-联二噻吩(3)为起始原料,通过丁基锂拔溴,氯化铜氧化偶联制备主产物环八四噻吩(TMS_4-COTh-1)和副产物环十二六噻吩(TMS_6-2).通过改变反应溶剂,即由乙醚改变为四氢呋喃,伴随副产物TMS_6-2的消失,制备TMS_4-COTh-1的产率从之前报道的40%提升至69%,表现出溶剂对反应的高效选择性.机理分析认为中间体二锂联噻吩的二聚体与三聚体在乙醚与四氢呋喃中的存在形式不同是造成产物分布不同的根本原因.Using 2,2′-dibromo-5,5′-bis（trimethylsilyl）-3,3′-bithiophene（3）as starting material,the main product cyclooctatetrathiophene（TMS4-COTh-1）and the side product cyclododecahexathiophene（TMS6-2）were obtained by Br/Li exchange and following copper（II）chloride oxidative coupling.By changing the reaction solvent from diethyl ether to tetrahydrofuran,the yields of TMS4-COTh-1 were improved from the reported 40%to 69%,while the side product TMS6-2 was disappeared.This reaction shows high efficient solvent-selectivity.Through the analysis of the reaction mechanism,it is concluded that the formation of intermediate dimer and/or trimer of 2,2′-dilithium-5,5′-bis（trimethylsilyl）-3,3′-bithiophene in diethyl ether or tetrahydrofuran is the key factor for the distribution of dimeric and trimeric products.

关 键 词：3 3′-联二噻吩 环八[1 2-b 3-b′ 6-b″ 7-b′″]四噻吩 氧化偶联 选择性 

分 类 号：O62[理学—有机化学]