Institut für Anorganische und Analytische Chemie, Friedrich-Schiller-Universität Jena, August-Bebel-Str. 2, D-07743, Jena, Germany.
Dalton Trans. 2010 Jun 14;39(22):5356-66. doi: 10.1039/b926723a. Epub 2010 May 6.
The deprotonation of (2-pyridylmethyl)(triorganylsilyl)amines of the type Py-CH(2)-N(H)-SiR(3) with SiR(3) = SiMe(2)tBu (1a), SiMe(2)(CMe(2)iPr) (1b), SiiPr(3) (1c) and SiPh(3) (1d) with (thf)FeN(SiMe(3))(2)Cl in THF is accompanied by redox reactions and leads to the formation of iron(II) compounds. The products with lower solubility precipitated first and are the pale yellow and paramagnetic complexes chloro-(2-pyridylmethyl)(triorganylsilyl)amido iron(ii) [SiR(3) = SiMe(2)tBu (2a), SiMe(2)(CMe(2)iPr) (2b), SiiPr(3) (2c), and SiPh(3) (2d)]. These complexes crystallized dimeric with Fe(2)N(2) rings with different Fe-N bond lengths (average values of 211.1 and 203.2 pm). The Fe-Cl distances vary around an average value of 225.6 pm. Another isolated product consists of orange to blue crystals of dichloro-(2-pyridylmethylidene)(triorganylsilyl)amino iron(II) [SiR(3) = SiMe(2)tBu (3a), SiMe(2)(CMe(2)iPr) (3b), SiiPr(3) (3c), and SiPh(3) (3d)] which are obtained from very concentrated reaction solutions. These (2-pyridylmethylidene)(triorganylsilyl)amino ligands (imines) act as bidentate bases at FeCl(2) with average Fe-N and Fe-Cl bond lengths of 211.8 and 223.5 pm, respectively. The metallation of the (2-pyridylmethyl)(triorganylsilyl)amines with dimeric FeN(SiMe(3))(2) yields homoleptic iron(II) bis[(2-pyridylmethyl)(triorganylsilyl)amides] (4) with distorted tetrahedrally coordinated iron centers. Metathesis reactions of FeCl(3) with lithium (2-pyridylmethyl)(triorganylsilyl)amide as well as employing a mixture of FeN(SiMe(3))(2) and FeCl(3) with (2-pyridylmethyl)(triorganylsilyl)amine give similar results and the formation of chloro-(2-pyridylmethyl)(triorganylsilyl)amido iron(II) (2) and dichloro-(2-pyridylmethylidene)(triorganylsilyl)amino iron(II) (3) are observed.
(2-吡啶甲基)(三有机硅基)胺与 SiR3= SiMe2tBu(1a)、SiMe2(CMe2iPr)(1b)、SiiPr3(1c)和 SiPh3(1d)的脱质子反应伴随着氧化还原反应,并导致铁(II)化合物的形成。溶解度较低的产物首先沉淀出来,是淡黄色的顺磁性配合物氯-(2-吡啶甲基)(三有机硅基)酰胺铁(II)[SiR3= SiMe2tBu(2a)、SiMe2(CMe2iPr)(2b)、SiiPr3(2c)和 SiPh3(2d)]。这些配合物结晶为二聚体,具有不同 Fe-N 键长的 Fe2N2环(平均值为 211.1 和 203.2 pm)。Fe-Cl 距离约为 225.6 pm 的平均值。另一个分离产物由橙色到蓝色的二氯-(2-吡啶亚甲基)(三有机硅基)氨基铁(II)[SiR3= SiMe2tBu(3a)、SiMe2(CMe2iPr)(3b)、SiiPr3(3c)和 SiPh3(3d)]组成,这些产物是从非常浓的反应溶液中获得的。这些(2-吡啶亚甲基)(三有机硅基)氨基配体(亚胺)在 FeCl2中作为双齿碱,具有平均 Fe-N 和 Fe-Cl 键长分别为 211.8 和 223.5 pm。(2-吡啶甲基)(三有机硅基)胺与二聚体 Fe[N(SiMe3)2]2的金属化反应生成具有扭曲四面体配位铁中心的同核铁(II)双[(2-吡啶甲基)(三有机硅基)酰胺](4)。FeCl3与锂(2-吡啶甲基)(三有机硅基)酰胺的复分解反应以及使用 Fe[N(SiMe3)2]2和 FeCl3与(2-吡啶甲基)(三有机硅基)胺的混合物也得到类似的结果,并观察到氯-(2-吡啶甲基)(三有机硅基)酰胺铁(II)(2)和二氯-(2-吡啶亚甲基)(三有机硅基)氨基铁(II)(3)的形成。