A catalytic system for the synthesis of dicarboxylic acids from aqueous solutions of diols accompanied by the evolution of hydrogen was developed. An iridium complex bearing a functional bipyridonate ligand with N ,N‐dimethylamino substituents exhibited a high catalytic performance for this type of dehydrogenative reaction. For example, adipic acid was synthesized from an aqueous solution of 1,6‐hexanediol in 97 % yield accompanied by the evolution of four equivalents of hydrogen by the present catalytic system. It should be noted that the simultaneous production of industrially important dicarboxylic acids and hydrogen, which is useful as an energy carrier, was achieved. In addition, the selective dehydrogenative oxidation of vicinal diols to give α‐hydroxycarboxylic acids was also accomplished.

中文翻译：

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铱络合物催化析氢从二醇水溶液合成二羧酸。

开发了一种从二醇水溶液合成二羧酸并伴随氢气放出的催化系统。带有N , N-二甲氨基取代基的功能性联吡啶酮配体的铱络合物对此类脱氢反应表现出高催化性能。例如，由 1,6-己二醇水溶液合成己二酸，收率达 97%，同时通过本催化系统放出四当量的氢气。值得注意的是，工业上重要的二羧酸和可用作能量载体的氢气的同时生产已实现。此外，还完成了邻二醇选择性脱氢氧化生成α-羟基羧酸。