4-diaryl- and 2,3-diarylthiophenes were synthesized from 2,5-dichlorothiophene via 4-aryl-2-chlorothiophenes in two and four steps including Ni-mediated cross-coupling, respectively. Aluminumchloride-catalyzedreaction of 3-aryl-2-chlorothiophenes with some aromatic ethers unexpectedly led to the formation of the corresponding 2,4-isomers.
不对称取代的 2,4-二芳基-和 2,3-二芳基噻吩分别由 2,5-二氯噻吩通过 4-芳基-2-氯噻吩在两步和四步(包括 Ni 介导的交叉偶联)中合成。氯化铝催化的 3-芳基-2-氯噻吩与一些芳香醚的反应出人意料地导致了相应的 2,4-异构体的形成。
Synthesis of 3,4′-Diaryl- and 4,4′-Diaryl-2,2′-bithienyls from 2,5-Dichlorothiophene
作者:Tyo Sone、Yasuhiro Umetsu、Kazuaki Sato
DOI:10.1246/bcsj.64.864
日期:1991.3
3,4′-Diaryl-, and 4,4′-diaryl-2,2′-bithienyls, new classes of mixed thiophene–arene oligomers, were synthesized from 2,5-dichlorothiophene via 4-aryl-2-chlorothiophene in three and two steps, respectively. Namely, a Friedel–Crafts type self-condensation of 4-aryl-2-chlorothiophene, followed by catalytic dechlorination, yielded unsymmetrical bithienyls. Homocoupling of 4-aryl-2-chlorothiophene using