Several new 3‐(hetero)aryl‐2‐phenylthieno[3, 2‐b]pyridines and 7‐(hetero)aryl‐6‐phenyl thieno[2, 3‐b]pyrazines were prepared by Suzuki cross‐coupling of 3‐bromo‐2‐phenylthieno[3, 2‐b]pyridine and 7‐bromo‐6‐phenylthieno[2, 3‐b]pyrazine and (hetero)arylboronic acids after optimization of the reaction conditions, in moderate to excellent yields. The 3‐ and 7‐brominated compounds were prepared by bromination using Br₂ in CH₂Cl₂ at 0 °C of the 2‐phenylthieno[3, 2‐b]pyridine and 6‐phenylthieno[2, 3‐b]pyrazine, respectively. The latter were synthesized in a two‐step one‐pot procedure by Pd/Cu catalyzed Sonogashira coupling of 2‐bromo‐3‐chloropyridine or 2,3‐dichloropyrazine with phenylacetylene, followed by treatment with Na₂S. We show the wide scope of the synthesis of Suzuki cross‐coupling products, after optimization of the reaction conditions, from both brominated biheterocyclic systems and different (hetero)arylboronic acids. The final compounds may show interesting biological activity.

中文翻译：

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钯交叉偶联合成新的噻吩并[3,2-b]吡啶和噻吩并[2,3-b]吡啶。

通过Suzuki的3-（3-（杂）芳基-2-苯基]噻吩并[3,2- b ]吡啶和7-（杂）芳基-6-苯基噻吩并[2,3- b ]吡嗪的制备优化反应条件后，溴化-2-苯基噻吩并[3,2- b ]吡啶和7-溴-6-苯基噻吩并[2,3- b ]吡嗪和（杂）芳基硼酸的产率中等至优异。通过在₂ ° CH ₂ Cl ₂中的Br ₂在₂ °C的噻吩并[3，2 b ]吡啶和6-苯基的噻吩[2，3- b分别为]吡嗪。后者通过Pd / Cu催化2-溴3-氯代吡啶或2,3-二氯吡嗪与苯乙炔的Pd / Cu催化Sonogashira偶联，然后用Na ₂ S处理，以两步一锅法合成。优化反应条件后，由溴化双杂环体系和不同的（杂）芳基硼酸合成铃木交叉偶联产物的方法 最终化合物可能显示出令人感兴趣的生物学活性。