Studies on the preference of multiple coupling in the introduction of thiophene ring into poly-halogenated aromatic compounds with nickel NHC catalyst
作者:Shota Tanaka、Go Tatsuta、Atsushi Sugie、Atsunori Mori
DOI:10.1016/j.tetlet.2013.01.127
日期:2013.4
Several thiophene derivatives can be deprotonated by the combination of ethyl magnesium chloride (EtMgCl) and a catalytic amount of 2,2,6,6-tetramethylpiperidine (TMP-H). The metalated 3-hexylthiophene reacts with 2,3- and 2,5-dibromothiophenes in the presence of a nickel catalyst bearing NHC ligand (IPr) to afford the di-coupled product exclusively along with recovery of dibromothiophene albeit the
几种
噻吩衍
生物可以通过
乙基氯化镁(EtMgCl)和催化量的
2,2,6,6-四甲基哌啶(
TMP-H)结合而去质子化。在具有NHC
配体(IPr)的
镍催化剂存在下,
金属化的
3-己基噻吩与2,3-和
2,5-二溴噻吩反应,以提供二偶联产物,尽管等摩尔反应,但仅与二
溴噻吩的回收一起提供。
3-己基噻吩与二
溴代苯衍
生物的1:1反应也可得到双偶合产物作为唯一产物。