First-row transition metal bis(amidinate) complexes;: Planar four-coordination of FeII enforced by sterically demanding aryl substituents

被引:62
作者
Nijhuis, CA
Jellema, E
Sciarone, TJJ
Meetsma, A
Budzelaar, PHM
Hessen, B
机构
[1] Univ Groningen, Dutch Polymer Inst, Ctr Catalyt Olefin Polymerisat, Stratingh Inst Chem & Chem Engn, NL-9747 AG Groningen, Netherlands
[2] Radboud Univ Nijmegen, Dutch Polymer Inst, Inst Mol & Mat Met Organ Chem, NL-6500 GL Nijmegen, Netherlands
关键词
transition metals; solid-state structures; ligand effects; amidinate; density functional calculations;
D O I
10.1002/ejic.200500094
中图分类号
O61 [无机化学];
学科分类号
070301 ; 081704 ;
摘要
The sterically hindered benzamidinate ligand [PhC(NAr)(2)](-) (Ar = 2,6-iPr(2)C(6)H(3)) has been employed to prepare bis(amidinate) complexes [{PhC(NAr)(2)}(2)M] of the divalent first-row transition metals Cr-Ni (1-5). For Cr (planar), Mn and Co (tetrahedral) the observed structures follow the electronic preference for the metal ion in its highest spin multiplicity, as determined by DFT calculations. Remarkably, the Fe derivative adopts a distorted planar structure while retaining the high-spin (S = 2) configuration. This rare combination due to reduced interligand steric interactions in the planar vs. the tetrahedral structure, combined with a relatively small electronic preference of Fen for the tetrahedral environment. Thus, the simple bidentate ligand N,N '-diarylbenzamidinate provides a convenient means to make this unusual species accessible for further study. (c) Wiley-VCH Verlag GmbH & Co.
引用
收藏
页码:2089 / 2099
页数:11
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