等离子体引发CH3OH/NH3偶联反应合成腈类化合物

腈类化合物广泛用于医药和精细化学品合成。然而，许多腈类的生产过程产生大量污染物。本文采用介质阻挡放电(DBD)等离子体活化甲醇和氨气分子，发现等离子体引发的CH₃OH/NH₃偶联反应可合成二甲基氰胺、二甲基氨基乙腈和氨基乙腈等高附加值含N有机化合物。系统研究了反应器结构、放电条件、反应条件和填充材料对甲醇转化率和产物选择性的影响。实验结果表明，在最优条件下，甲醇的转化率达到51.5%，腈类化合物选择性达到22.1%。CH₃OH/NH₃等离子体发射光谱结果表明，C≡N自由基物种可能是生成腈类化合物的重要中间体。该CH₃OH/NH₃等离子体偶联反应为二甲基氰胺、二甲基氨基乙腈和氨基乙腈提供了一种绿色合成方法，也为甲醇和氨气精细化利用开辟了一种新途径。

Plasma-Triggered CH3OH/NH3 Coupling Reaction for Synthesis of Nitrile Compounds

Nitriles are very important for the synthesis of fine chemicals and medicines. However, many nitriles are not widely available, as their synthesis processes pose a serious risk to the environment. Herein, we report that a spontaneous CH₃OH/NH₃ coupling reaction can directly synthesize N, N-dimethyl cyanamide(CH₃)₂NCN], amino acetonitrile NH₂CH₂CN], and N, N-dimethyl amino acetonitrile (CH₃)₂NCH₂CN], when a mixture of methanol and ammonia is transferred into the plasma state via a dielectric barrier discharge. The effects of the plasma reactor configuration, discharge conditions, reaction conditions, and packing materials on the methanol conversion as well as the product selectivity were systematically investigated. Experimental results indicate that, under optimized conditions, a nitrile compound selectivity of 22.1% with a methanol conversion of 51.5% could be achieved. Analysis by optical emission spectroscopy indicates that the C≡N species in CH₃OH/NH₃ plasma could be a key reactive intermediate aiding in the synthesis of nitrile compounds. The CH₃OH/NH₃ plasma coupling reaction process is an environment-friendly methodology for the synthesis of (CH₃)₂NCN, NH₂CH₂CN, and (CH₃)₂NCH₂CN, and is a potential novel pathway for the synthesis of fine chemicals like methanol and ammonia.