含2,6 - 二（苯基亚氨基）哌啶阴离子的线性三铬配合物

Linear trichromium complexes with the anion of 2,6-di(phenylimino)piperidine.

作者信息

Clérac R, Cotton F A, Daniels L M, Dunbar K R, Murillo C A, Zhou H C

机构信息

Laboratory for Molecular Structure and Bonding, Department of Chemistry, P.O. Box 30012, Texas A&M University, College Station, Texas 77842-3012, USA.

出版信息

Inorg Chem. 2000 Jul 24;39(15):3414-7. doi: 10.1021/ic0001964.

DOI:10.1021/ic0001964

PMID:11196882

Abstract

The anion of 2,6-di(phenylimino)piperidine (DPhIP) has been found to support linear chains of three metal atoms. Three new compounds, [Cr3(DPhIP)4Cl]Cl.(1).5CH2Cl2.0.5H2O (1.1.5CH2Cl2.0.5H2O), [Cr3(DPhIP)4(CH3CN)]- (PF6)2.H2O.4CH3CN (2.H2O.4CH3CN), and Cr3(DPhIP)4(F)(CH3CN)2.5CH3CN (3.5CH3CN), have been synthesized and characterized by X-ray crystallography. Compound 1 has a linear chain of three chromium atoms arranged in an unsymmetrical fashion, with two of them forming a quadruply bonded unit (Cr-Cr distance 1.932(2) A) and the third being a non-metal-metal-bound 5-coordinate unit (Cr...Cr distance 2.659(2) A). The fifth coordination site is occupied by a chloride ion, and another chloride ion is located in the interstices of the crystal. The trimetal unit in compound 2 is structurally similar to that in compound 1 except that the axial ligand in 2 is a CH3CN molecule. Compound 3 is an oxidation product prepared by reaction of 1 with AgBF4. Here, a square pyramidal CrIII unit, FCrN4, and a Cr-Cr quadruply bonded (Cr-Cr distance 1.968(2) A) unit, with an axially coordinated acetonitrile molecule, form the trichromium chain. The CrIII...CrII separation of 2.594(2) A in 3 is too long to be considered a bonding interaction.

摘要

已发现2,6 - 二（苯基亚氨基）哌啶（DPhIP）的阴离子能支持由三个金属原子组成的线性链。合成了三种新化合物，[Cr₃(DPhIP)₄Cl]Cl·(1)·5CH₂Cl₂·0.5H₂O (1·1.5CH₂Cl₂·0.5H₂O)、Cr₃(DPhIP)₄(CH₃CN)₂·H₂O·4CH₃CN (2·H₂O·4CH₃CN) 和 Cr₃(DPhIP)₄(F)(CH₃CN)₂·5CH₃CN (3·5CH₃CN)，并通过X射线晶体学对其进行了表征。化合物1具有由三个铬原子组成的呈不对称排列的线性链，其中两个铬原子形成一个四重键单元（Cr - Cr距离为1.932(2) Å），第三个是一个通过非金属 - 金属键连接的五配位单元（Cr...Cr距离为2.659(2) Å）。第五个配位点被一个氯离子占据，另一个氯离子位于晶体的间隙中。化合物2中的三金属单元在结构上与化合物1中的相似，只是2中的轴向配体是一个CH₃CN分子。化合物3是通过1与AgBF₄反应制备的氧化产物。在此，一个四方锥型的CrIII单元，FCrN₄，以及一个具有轴向配位乙腈分子的Cr - Cr四重键（Cr - Cr距离为1.968(2) Å）单元，形成了三铬链。化合物3中CrIII...CrII的间距为2.594(2) Å，太长以至于不能被认为是一种键合相互作用。