Cu(II)-Ion-Catalyzed Solvolysis of <i>N,N-</i>Bis(2-picolyl)ureas in Alcohol Solvents: Evidence for Cleavage Involving Nucleophilic Addition and Strong Assistance of Bis(2-picolyl)amine Leaving Group Departure
作者:Mei-Ni Belzile、Alexei. A. Neverov、R. Stan Brown
DOI:10.1021/ic500620k
日期:2014.8.4
observed products. The reactions also proceed in other solvents, with the order of reactivity ethanol > methanol >1-propanol >2-propanol > acetonitrile (with 0.2% methanol) > water spanning a range of 150-fold. The mechanism of the reactions is discussed, and the reactivity and mode of cleavage are compared with that of the M(II)-promoted ethanolytic cleavage of a mono-2-picolyl derivative, N-p-nit
用于溶剂分解的动力学和产品ñ - p -nitrophenyl- Ñ ',Ñ ' -双(吡啶-2-基甲基)脲(图7a),Ñ甲基ñ - p -nitrophenyl- Ñ ',Ñ双(吡啶-2-基甲基)尿素(7b)以及在甲醇和甲醇中由Cu(II)离子促进的N-苯基-N ',N'-双(吡啶-2-基甲基)尿素(DPPU)(7c)在s s下研究了乙醇在25°C下控制pH的条件。这些底物的甲醇解和乙醇化反应以底物:金属离子的1:1比例快速进行,在甲醇中Cu(II):7a络合物分解的半衰期约为150分钟,在乙醇中约为15分钟。在所有情况下,反应产物都是双(2-吡啶甲基)胺的Cu(II)配合物和母体苯胺的氨基甲酸O-甲基或O-乙基氨基甲酸酯,这表明裂解点是双(2-吡啶甲基) )—N—C═O键。在每种溶剂中,Cu(II):7b配合物的反应比其各自的Cu(II):7a的反应慢约3-5倍不包括消除机制,该消除机