New methods for the synthesis of 4<i>H</i>
-dithieno[3,2-<i>b</i>
:2′,3′-<i>d</i>
]pyrrole
作者:Sebastian Förtsch、Astrid Vogt、Peter Bäuerle
DOI:10.1002/poc.3743
日期:2017.9
Various alternative methods for the synthesis of 4H‐dithieno[3,2‐b:2′,3′‐d]pyrrole (DTP) starting from commercially available bromothiophene precursors are presented. Crucial steps involve the Cadogan reaction, Ullmann‐type C─N couplings, or Buchwald‐Hartwig–type aminations to build up the central pyrrole ring of DTP, respectively. The use of ammonia surrogates afforded the fused target heteroacene
提出了从商业上可获得的溴噻吩前体开始合成4 H- dithieno [3,2- b:2',3'- d ]吡咯(DTP)的各种替代方法。关键步骤涉及Cadogan反应,Ullmann型C-N偶联或Buchwald-Hartwig型胺化,以建立DTP的中心吡咯环。使用氨代孕盐可得到总目标产率为33%至63%的稠合目标杂并苯,并且相应的方法可大规模应用。