An efficient route for the coupling of maleimides with chromones at the C5-position has been developed under Ru(II) catalysis. It could provide 1,4-addition products and oxidative Heck-type products by switching additives. Benzoic acid led to the formation of 1,4-addition products under solvent-free conditions, and silver acetate was promoted to the generation of oxidative Heck-type products. Various maleimides and chromones were suitable for this transformation, affording the desired products with good to excellent yields in a short reaction time. To understand the mechanism of this reaction, deuteration studies and control experiments have been performed.

中文翻译：

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钌（II）催化的马来酰亚胺苯并二氢吡喃酮对CH的活化，以合成琥珀酰亚胺/马来酰亚胺并含苯二酚。

在Ru（II）催化下，已经开发了马来酰亚胺与色酮在C5位偶联的有效途径。通过切换添加剂可以提供1，4-加成产物和氧化性Heck型产物。在无溶剂条件下，苯甲酸导致形成1，4-加成产物，乙酸银被促进生成氧化型Heck型产物。各种马来酰亚胺和色酮适合于该转化，在短的反应时间内以良好至优异的产率提供所需的产物。为了理解该反应的机理，已经进行了氘化研究和对照实验。