Constructing a Catalytic Cycle for C–F to C–X (X = O, S, N) Bond Transformation Based on Gold-Mediated Ligand Nucleophilic Attack
作者:Ji-Yun Hu、Jing Zhang、Gao-Xiang Wang、Hao-Ling Sun、Jun-Long Zhang
DOI:10.1021/acs.inorgchem.5b02634
日期:2016.3.7
replacement of Cl by a more nucleophilic tBuO anion ligand, showed higher reactivity and para selectivity in the transformation of C–F to C–OtBu bond, distinctively different from that when only KOtBu was used (ortho selectivity) under the identical condition. Mechanistic studies including density functional theory calculations suggested a gold-mediated nucleophilic ligand attack of the C–F bond pathway
三配位氯化金(I)络合物tBuXantphosAuCl,由空间庞大的9,9-二甲基-4,5-双(二叔丁基)支撑合成了丁基丁基膦基)的蒽酮配体(tBuXantphos)。该络合物的特征是与双配位线性金络合物(2.27–2.30Å)和三配位XantphosAuCl [2.462(1)Å]相比,Au–Cl键长[2.632(1)Å]长得多。tBuXantphosAuCl和五氟硝基苯(PFNB)的共晶体的单晶X射线衍射分析和紫外可见分光光度法滴定实验表明,Cl阴离子配体与PFNB之间存在阴离子-π相互作用。PFNB与tBuXantphosAuOtBu之间的化学计量反应在被更具亲核性的tBuO阴离子配体取代Cl后,在C–F向C–OtBu键的转化中表现出更高的反应性和对位选择性,这与仅使用KOtBu时显着不同(邻位选择性) )在相同的条件下。N Ar工艺。根据这些结果,使用三甲基甲硅烷基衍生物TMS-X(X