Direct Oxidative Cyanation of Alcohol to Nitrile over CoOx/MnO2 with Aqueous Ammonia
Direct Oxidative Cyanation of Alcohol to Nitrile over CoOx/MnO2 with Aqueous Ammonia
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DOI：
10.1021/acssuschemeng.2c05205
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发表时间：
2022-10
期刊：
影响因子：
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通讯作者：
Weitao Wang;Liqiong Ma;Xulu Jiang;Huan Wang;Zhen‐Hong He;Kuan Wang;Yang Yang-Yang;Zhao‐Tie Liu
中科院分区：
文献类型：
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作者：
Weitao Wang;Liqiong Ma;Xulu Jiang;Huan Wang;Zhen‐Hong He;Kuan Wang;Yang Yang-Yang;Zhao‐Tie Liu
醇的高度直接氧化氰化为无氰合成有机腈提供了一条很有前途的合成路线。氨条件下醇直接转化为腈是一个三步连续反应，因此探索无贵金属催化剂具有挑战性。在氨水存在下，CoOx/MnO 2催化剂用于苯甲醇直接氧化氰化合成苯甲腈，收率为86%，选择性为91%。可以通过水加速苯甲腈向苯甲酰胺的转化来调节对苯甲腈和苯甲酰胺的选择性。此外，动力学研究表明，苯甲醇氧化的第一步是后续反应的速率控制步骤。发现Mn物种是该反应的主要活性中心，Co物种是该反应的助催化剂。此外，在本催化体系中使用的起始底物可以扩展到脂肪族、苄基、烯丙基和杂环醇，这证明了从醇直接合成腈的可持续策略，同时避免使用常规的有毒氰化物。
Highly direct oxidative cyanation of alcohols provides a promising synthesis route for the cyanide-free synthesis of organic nitriles. It is challenging to explore a noble metal-free catalyst for direct conversion of alcohol to nitrile under ammonia conditions because it is a three-step consecutive reaction. In the present work, the CoOx/MnO2catalyst was developed for direct oxidative cyanation of benzyl alcohol to benzonitrile with a yield of 86% and a selectivity of 91% with aqueous ammonia. The selectivity to benzonitrile and benzamide can be tuned via water accelerating the transformation of benzonitrile to benzamide. In addition, the kinetic studies reveal that the first step of the oxidation of benzyl alcohol is the rate-determining step for the consecutive reactions. It is found that Mn species are the main active sites while Co species are the co-catalyst for the titled reaction. Moreover, the starting substrates employed in the present catalytic system can be expanded to aliphatic, benzylic, allylic, and heterocyclic alcohols, which demonstrates a sustainable strategy for the direct synthesis of nitrile from alcohol while avoiding the use of the conventional toxic cyanide.