Bis(ortho-)chelated Monoanionic Bisphosphinoaryl Ruthenium(II) Complexes: Synthesis, Characterization and Reactivity

Bisphosphinoaryl ruthenium(Ⅱ) compounds are synthesized using two distinctsynthetic routes. One route, direct cycloruthenation, consists of the reaction of the parent arenecompound R-PCHP with [RuCl_2 (PPh_3)_3] in chlorinated solvents. However, this route suffers frommajor drawbacks because HCl is formed as well as free triphenylphoshine. The other route, thetranscyclometalation reaction, involves the interconversion of one cyclometalated ligand metalcomplex, [RuCl (NCN) (PPh_3)], into another complex, [RuCl (R-PCP) (PPh_3)], with concomitantconsumption and formation of the corresponding arenes R-PCHP and NCHN, respectively.

一维[Pd(mnt)_2]-自旋体系磁交换作用的密度泛函理论(DFT)分析(英文)

4个一维磁链化合物[R-BzPy][Pd(mnt)2](R-BzPy+=对位取代苄基吡啶阳离子;R=Cl(化合物1),Br(化合物2),I(化合物3)和NO2(化合物4))具有相似的晶体堆积结构,即,[Pd(mnt)2]-和R-BzPy+分别形成完全分列的柱状堆积。这一结构特征与其类似化合物[R-BzPy][Ni(mnt)2]相似。但是,[Pd(mnt)2]-和[Ni(mnt)2]-2个系列化合物结构之间存在明显差异:(1)室温下,[R-BzPy][Ni(mnt)2]晶体中[Ni(mnt)2]-和R-BzPy+堆积柱是均匀的;而[R-BzPy][Pd(mnt)2]晶体中[Pd(mnt)2]-和R-BzPy+堆积柱是不均匀的。(2)在两个系列化合物阴离子堆积柱内,相邻[Pd(mnt)2]-分子平面之间距离比相邻[Ni(mnt)2]-分子平面之间距离短。在[Pd(mnt)2]-堆积柱内,[Pd(mnt)2]-离子之间反铁磁交换作用非常强,导致了化合物几乎呈抗磁性。在密度泛函理论框架下,利用对称性破损方法,我们计算了[Pd(mnt)2]-离子之间磁交换常数。在svwn/lanl2dz和bpw91/lanl2dz水平上的计算结果与磁化率拟合结果一致。理论分析揭示,在[Pd(mnt)2]-堆积柱内,[Pd(mnt)2]-离子之间强反铁磁交换与其π-型前线轨道有效重叠密切相关。