Caballo Jorge, Greño Maider, Mena Miguel, Pérez-Redondo Adrián, Yélamos Carlos
Departamento de Química Orgánica y Química Inorgánica, Universidad de Alcalá, 28871 Alcalá de Henares-Madrid, Spain.
Dalton Trans. 2015 Nov 7;44(41):18145-57. doi: 10.1039/c5dt02836a. Epub 2015 Sep 30.
Treatment of [{Ti(η(5)-C5Me5)(μ-NH)}3(μ3-N)] (1) with zirconium or hafnium tetrachloride adducts [MCl4(thf)2] affords complexes [Cl3M{(μ3-N)(μ3-NH)2Ti3(η(5)-C5Me5)3(μ3-N)}] (M = Zr (2), Hf (3)). Titanium chloride complexes [Cl2Ti{(μ3-N)2(μ3-NH)Ti3(η(5)-C5Me5)3(μ3-N)}] (4) and [(Me2NH)ClTi{(μ3-N)3Ti3(η(5)-C5Me5)3(μ3-N)}] (5) are obtained by reaction of 1 with [TiCl4-x(NMe2)x] (x = 2, 3). The dimethylamine ligand in 5 is displaced by pyridine to give the analogue complex [(py)2ClTi{(μ3-N)3Ti3(η(5)-C5Me5)3(μ3-N)}] (6). Treatment of the titanium chloride complexes 4 and 5 with sodium cyclopentadienide or lithium bis(trimethylsilyl)amide reagents leads to the cube-type nitrido derivatives [RTi{(μ3-N)3Ti3(η(5)-C5Me5)3(μ3-N)}] (R = η(5)-C5H5 (7), N(SiMe3)2 (8)). The reaction of the zirconium trichloride complex 2 with [Tl(C5H5)] yields exclusively the dichloride-monocyclopentadienyl derivative [(η(5)-C5H5)Cl2Zr{(μ3-N)(μ3-NH)2Ti3(η(5)-C5Me5)3(μ3-N)}] (9). However, the treatment of 2 with excess [Na(C5H5)] causes further chloride replacement in 9 and subsequent cyclopentadiene elimination to give [(η(5)-C5H5)Zr{(μ3-N)3Ti3(η(5)-C5Me5)3(μ3-N)}] (10) via intermediates [(η(5)-C5H5)2ClZr{(μ3-N)Ti3(η(5)-C5Me5)3(μ-NH)2(μ3-N)}] (11) and [(η(5)-C5H5)ClZr{(μ3-N)2(μ3-NH)Ti3(η(5)-C5Me5)3(μ3-N)}] (12). Treatment of 2 or 9 with [Mg(C5H5)2] leads to the magnesium derivative [(η(5)-C5H5)Mg(μ-Cl)2(η(5)-C5H5)Zr{(μ4-N)(μ3-N)(μ3-NH)Ti3(η(5)-C5Me5)3(μ3-N)}] (13), which can be visualized as a result of the incorporation of one [Mg(η(5)-C5H5)Cl] moiety to complex 12. In contrast to the metathesis process with [M(C5H5)x] derivatives and subsequent C5H6 eliminations, the reaction of 2 with potassium pentamethylcyclopentadienide in toluene produces the paramagnetic derivative [K(μ-Cl)3Zr{(μ3-N)(μ3-NH)2Ti3(η(5)-C5Me5)3(μ3-N)}] (14) and C10Me10. Complex 14 reacts with one equivalent of 18-crown-6 or cryptand-222 to give the molecular complex [(18-crown-6)K(μ-Cl)3Zr{(μ3-N)(μ3-NH)2Ti3(η(5)-C5Me5)3(μ3-N)}] (15) or the ion pair [K(crypt-222)][Cl3Zr{(μ3-N)(μ3-NH)2Ti3(η(5)-C5Me5)3(μ3-N)}] (16). The X-ray crystal structures of 2, 8, 13 and 15 have been determined.
用四氯化锆或四氯化铪加合物[MCl₄(thf)₂]处理[{Ti(η⁵ - C₅Me₅)(μ - NH)}₃(μ₃ - N)] (1)，得到配合物[Cl₃M{(μ₃ - N)(μ₃ - NH)₂Ti₃(η⁵ - C₅Me₅)₃(μ₃ - N)}] (M = Zr (2), Hf (3))。通过1与[TiCl₄₋ₓ(NMe₂)ₓ] (x = 2, 3)反应得到氯化钛配合物[Cl₂Ti{(μ₃ - N)₂(μ₃ - NH)Ti₃(η⁵ - C₅Me₅)₃(μ₃ - N)}] (4)和[(Me₂NH)ClTi{(μ₃ - N)₃Ti₃(η⁵ - C₅Me₅)₃(μ₃ - N)}] (5)。5中的二甲胺配体被吡啶取代，得到类似的配合物[(py)₂ClTi{(μ₃ - N)₃Ti₃(η⁵ - C₅Me₅)₃(μ₃ - N)}] (6)。用环戊二烯基钠或双(三甲基硅基)酰胺锂试剂处理氯化钛配合物4和5，得到立方型氮化物衍生物[RTi{(μ₃ - N)₃Ti₃(η⁵ - C₅Me₅)₃(μ₃ - N)}] (R = η⁵ - C₅H₅ (7), N(SiMe₃)₂ (8))。三氯化锆配合物2与[Tl(C₅H₅)]反应，仅生成二氯化物 - 单环戊二烯基衍生物[(η⁵ - C₅H₅)Cl₂Zr{(μ₃ - N)(μ₃ - NH)₂Ti₃(η⁵ - C₅Me₅)₃(μ₃ - N)}] (9)。然而，用过量的[Na(C₅H₅)]处理2会导致9中进一步的氯取代以及随后环戊二烯的消除，通过中间体[(η⁵ - C₅H₅)₂ClZr{(μ₃ - N)Ti₃(η⁵ - C₅Me₅)₃(μ - NH)₂(μ₃ - N)}] (11)和[(η⁵ - C₅H₅)ClZr{(μ₃ - N)₂(μ₃ - NH)Ti₃(η⁵ - C₅Me₅)₃(μ₃ - N)}] (12)得到[(η⁵ - C₅H₅)Zr{(μ₃ - N)₃Ti₃(η⁵ - C₅Me₅)₃(μ₃ - N)}] (10)。用[Mg(C₅H₅)₂]处理2或9会得到镁衍生物[(η⁵ - C₅H₅)Mg(μ - Cl)₂(η⁵ - C₅H₅)Zr{(μ₄ - N)(μ₃ - N)(μ₃ - NH)Ti₃(η⁵ - C₅Me₅)₃(μ₃ - N)}] (13)，这可以看作是一个[Mg(η⁵ - C₅H₅)Cl]部分并入配合物12的结果。与用[M(C₅H₅)ₓ]衍生物进行复分解反应及随后的C₅H₆消除不同，2与五甲基环戊二烯基钾在甲苯中的反应生成顺磁性衍生物[K(μ - Cl)₃Zr{(μ₃ - N)(μ₃ - NH)₂Ti₃(η⁵ - C₅Me₅)₃(μ₃ - N)}] (14)和C₁₀Me₁₀。配合物14与一当量的18 - 冠 - 6或穴状配体 - 222反应，得到分子配合物[(18 - 冠 - 6)K(μ - Cl)₃Zr{(μ₃ - N)(μ₃ - NH)₂Ti₃(η⁵ - C₅Me₅)₃(μ₃ - N)}] (15)或离子对[K(穴 - 222)][Cl₃Zr{(μ₃ - N)(μ₃ - NH)₂Ti₃(η⁵ - C₅Me₅)₃(μ₃ - N)}] (16)。已测定了2、8、13和15的X射线晶体结构。
