Department of Chemistry , Purdue University , West Lafayette , Indiana 47907 , United States.
Inorg Chem. 2019 Feb 18;58(4):2618-2626. doi: 10.1021/acs.inorgchem.8b03216. Epub 2019 Jan 30.
Reported herein are the first examples of the formation of Ru-C bonds in paddlewheel diruthenium species. A series of six Ru( ap)(CH-4-X) type compounds ( ap = 2-anilinopyridinate; X = NMe (1), N,N-(CH-4-OMe) (2), Bu (3), H (4), Br (5), CF (6)) was synthesized by employing the lithium-halogen exchange reaction with a variety of para-substituted aryl halides. These compounds have been characterized via electronic absorption spectroscopy, cyclic voltammetry, mass spectrometry, and magnetism studies, and their molecular structures have been established by single-crystal X-ray diffraction studies. All compounds are in the Ru oxidation state, with a ground-state electronic configuration of σπδ(πδ). Crystal structures of 1-6 confirm this, indicating a Ru-Ru bond order of 2.5. Electrochemical data suggest that the σ-aryls are stronger donors than the σ-alkynyls. A range of electronically different substituents allows for a closer inspection of the extent of electronic conjugation across the diruthenium paddlewheel core and the axial aryl ligand.
本文报道了首例在桨轮型二钌物种中形成 Ru-C 键的实例。通过与各种对位取代的芳基卤化物的锂-卤交换反应，合成了一系列六种 Ru(ap)(CH-4-X)型化合物（ap = 2- 氨基吡啶；X = NMe（1），N，N-（CH-4-OMe）（2），Bu（3），H（4），Br（5），CF（6））。这些化合物通过电子吸收光谱、循环伏安法、质谱和磁性研究进行了表征，并通过单晶 X 射线衍射研究确定了它们的分子结构。所有化合物均处于 Ru 氧化态，基态电子构型为 σπδ(πδ)。1-6 的晶体结构证实了这一点，表明 Ru-Ru 键序为 2.5。电化学数据表明，σ-芳基比 σ-炔基的供电子能力更强。一系列电子性质不同的取代基允许更仔细地检查轴向芳基配体穿过二钌桨轮核心的电子共轭程度。
