Abteilung Anorganische Chemie, Institut für Chemie, Universität Rostock, Albert-Einstein-Straße 3a, D-18059 Rostock, Germany.
J Am Chem Soc. 2012 Oct 24;134(42):17757-68. doi: 10.1021/ja308104k. Epub 2012 Oct 10.
(Me(3)Si)(2)CNN isomerizes upon addition of traces of Me(3)Si ions to give (Me(3)Si)(2)NNC, which then undergoes an unusual trimerization reaction to give exclusively 4-diazenyl-3-hydrazinylpyrazole. As catalyst the isonitrilium ion, (Me(3)Si)(2)NNC(SiMe(3)), was identified and fully characterized. Experiments and computations indicate a three-step reaction including isomerization of diazomethane, a C-C or N-C coupling, and a formal cycloaddition reaction. The kinetics and thermodynamics are discussed on the basis of DFT calculations.
(Me(3)Si)(2)CNN 在加入痕量的 Me(3)Si 离子后发生异构化，生成(Me(3)Si)(2)NNC，然后发生异常的三聚反应，仅得到 4-二氮烯基-3-肼基吡唑。异腈鎓离子 (Me(3)Si)(2)NNC(SiMe(3)) 被鉴定为催化剂，并进行了充分的表征。实验和计算表明，该反应包括三步，包括重氮甲烷的异构化、C-C 或 N-C 偶联以及形式上的环加成反应。动力学和热力学是基于 DFT 计算讨论的。
