Pérez-Bitrián Alberto, Martínez-Salvador Sonia, Baya Miguel, Casas José M, Martín Antonio, Menjón Babil, Orduna Jesús
Instituto de Síntesis Química y Catálisis Homogénea (iSQCH), CSIC-Universidad de Zaragoza, C/ Pedro Cerbuna 12, 50009, Zaragoza, Spain.
Instituto de Ciencia de Materiales de Aragón (ICMA), CSIC-Universidad de Zaragoza, C/ Pedro Cerbuna 12, 50009, Zaragoza, Spain.
Chemistry. 2017 May 17;23(28):6919-6929. doi: 10.1002/chem.201700927. Epub 2017 Apr 24.
The homoleptic compound [PPh ][CF AuCF ] cleanly undergoes photoinduced oxidative addition of CF I to afford the organogold(III) derivative [PPh ][(CF ) AuI] in good yield and under mild conditions. This compound provides a convenient entry to the chemistry of the perfluorinated (CF ) Au fragment, the properties of which were analyzed with the aid of DFT methods and compared with those of the homologous non-fluorinated (CH ) Au moiety. It was found that reductive elimination of CX -CX in the former (X=F) requires a much higher energy barrier than in the latter (X=H) and is therefore considerably less favored. This can be considered as one of the main features underlying the significantly higher stability associated to the (CF ) Au fragment and its derivatives. This unsaturated, 14-electron species can be stabilized by coordination of any of the halide ligands, including fluoride. In fact, the whole series of anionic [PPh ][(CF ) AuX] complexes (X=F, Cl, Br, I, CN) has now been isolated and conveniently characterized. Evidence for intermolecular decomposition pathways upon thermolysis in the condensed phase is presented.
同配化合物[PPh ][CF AuCF ]能顺利地发生CF I的光致氧化加成反应，在温和条件下以良好的产率得到有机金(III)衍生物[PPh ][(CF ) AuI]。该化合物为研究全氟(CF ) Au片段的化学性质提供了一条便捷途径，借助密度泛函理论(DFT)方法对其性质进行了分析，并与同源的非氟化(CH ) Au部分的性质进行了比较。结果发现，前者(X = F)中CX - CX的还原消除所需的能垒比后者(X = H)高得多，因此不太容易发生。这可被视为与(CF ) Au片段及其衍生物相关的显著更高稳定性的主要特征之一。这种不饱和的14电子物种可通过任何卤化物配体（包括氟化物）的配位作用而稳定下来。事实上，现在已经分离并方便地表征了整个系列的阴离子型[PPh ][(CF ) AuX]配合物(X = F、Cl、Br、I、CN)。文中给出了在凝聚相中热解时分子间分解途径的证据。
