We describe a set of three fluorescent mesoionic benzo[4,5]imidazo-3-ide-[1,2-c]-2-alkyl-1,2,3-triazol-2-ium compounds obtained through a simple, concise and efficient synthetic sequence featuring a copper-catalyzed carbene–nitrene cyclization. The compounds were characterized by fluorescence spectroscopy highlighting promising photophysical properties in terms of quantum yields and Stokes shifts.
我们描述了一组通过简单,简洁的方法获得的三种荧光中性苯并[4,5]咪唑基-3-ide- [1,2 - c ] -2-烷基-1,2,3-三唑-2-鎓化合物高效的合成序列,具有铜催化的卡宾-丁二烯环化反应。通过荧光光谱对化合物进行表征,其在量子产率和斯托克斯位移方面突出了有前途的光物理性质。通过计算DFT和TD-DFT方法使实验性质合理化,并且与结构和光谱数据具有极好的一致性。
Di-Mesoionic Carbene-Bridged Complexes of Rh<sub>2</sub>, Ir<sub>2</sub>, and RhIr: A Stepwise Metalation Strategy for the Synthesis of di-MIC-Bridged Mixed-Metal Systems
作者:Matthew T. Zamora、Michael J. Ferguson、Martin Cowie
DOI:10.1021/om300423z
日期:2012.8.13
A meta-substituted benzene-bridged ditriazolium salt has been prepared using copper-catalyzed azide-alkyne cycloaddition (CuAAC or "click" chemistry) and methylation protocols. Metalation of this dicationic species by basic-ligand-containing [Rh(mu-OMe)(COD)](2) and [Ir(mu-OMe)(COD)](2) precursors provides homobimetallic complexes of Rh and Jr bridged by a 1,2,3-triazol-5-ylidene-type di-mesoionic carbene (di-MIC) via an "internal-base" strategy. By using only 1/2 equiv of the internal-base precursor, mononuclear MIC-anchored/pendent-triazolium intermediates have been isolated, in which only one end of the ditriazolium salt has been deprotonated and attached to Rh or Jr. Reaction of these pendent intermediates with another 1/2 equiv of an internal-base precursor affords either the aforementioned homobimetallic products or an analogous di-MIC-bridged, mixed-metal Ir/Rh complex.