Convenient Synthesis of α-Terthienyl and α-Quinquethienyl via a Friedel-Crafts Route
作者:Andreas Merz、Franz Ellinger
DOI:10.1055/s-1991-26494
日期:——
Thiophene and bithiophene are converted into 1,4-bis(2-thienyl)-1,4-butanedione and the corresponding bis(bithienyl) substituted diketone, respectively, by acylation with succinyl chloride/aluminum chloride in dichloromethane or 1,2-dichloroethane. Reaction of the diketones with Lawesson's reagent gives 2,2′: 5′,2″-terthiophene or 2,2′:5′,2″:5″,2′′′:5′′′,2′′′′-quinquethiophene (α -terthienyl or α-quinquethienyl) in high yields. Attempted acylation of α-terthienyl leads to 5,5-bis[5-(2,2′:5′,2″-terthienyl)] tetrahydrofuran-2-one. As a side-product of the Friedel-Crafts acylation of thiophene a new indigo-like blue dye with α-quaterthienyl framework is isolated.
噻吩和二噻吩通过在二氯甲烷或1,2-二氯乙烷中与琥珀酰氯/氯化铝进行酰化,转化为1,4-双(2-噻吩基)-1,4-丁二酮和相应的双(二噻吩基)取代的二酮。二酮与罗韦森试剂反应可以高产率地得到2,2′:5′,2″-三噻吩或2,2′:5′,2″:5″,2′′′:5′′′,2′′′′-五噻吩(α-三噻吩或α-五噻吩)。对α-三噻吩的酰化尝试导致5,5-双[5-(2,2′:5′,2″-三噻吩)]四氢呋喃-2-酮的形成。作为噻吩的弗里德尔-克拉夫茨酰化的副产物,分离出一种新型的类靛蓝蓝色染料,具有α-四噻吩骨架。