The role of new series of phosphine-free aurone ligands have been investigated in microwave-enhanced Mn (II) and Co (II) dehydrogenative coupling reactions. Various heterocyclic compounds such as Quinoline, pyridine, and pyrrole have been synthesized and characterized by NMR spectroscopy. The synthesized ligands (L1–L4) with Mn(II) and Co (II) salt showed excellent catalytic activity and proved to be very effective for the dehydrogenative coupling reaction. This synthetic method involves the in-situ formation of a metal ligand complex that was analyzed by mass spectrometry. A broad range of substrates including aliphatic ketone, heterocycles, and sterically hindered Ketone coupling partners are well tolerated in the developed protocol.

中文翻译：

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橙酮配体在微波增强Mn(II)和Co(II)催化脱氢偶联反应中的作用：合成喹啉、吡啶和吡咯的有效配体

研究人员研究了新系列无膦Aurone配体在微波增强Mn(II)和Co(II)脱氢偶联反应中的作用。各种杂环化合物如喹啉、吡啶和吡咯已被合成并通过核磁共振波谱进行表征。合成的Mn(II)和Co(II)盐配体( L1 – L4 )表现出优异的催化活性，并被证明对脱氢偶联反应非常有效。这种合成方法涉及金属配体络合物的原位形成，并通过质谱法进行分析。所开发的方案对多种底物（包括脂肪酮、杂环化合物和空间位阻酮偶联伙伴）具有良好的耐受性。