Bis(tetramethylcyclopentadienyl)titanium Chemistry. Molecular Structures of [(C₅HMe₄)(μ-η¹:η⁵-C₅Me₄)Ti]₂and [(C₅HMe₄)₂Ti]₂N₂

Abstract

Thermolysis of bis(tetramethylcyclopentadienyl)-stabilized titanium(III) compounds (C5HMe4)2TiR (R = Me (2), Ph (3)) yields, in marked contrast with the bis(pentamethylcyclopentadienyl) analog, the dimeric product [(C5HMe4)(μ-η1:η5-C5Me4)Ti]2 (4), with a bridging metalated tetramethylcyclopentadienyl ligand. The hydride (C5HMe4)2TiH (5), synthesized by hydrogenolysis of 2 or 3, reacts with N2 to form the dinuclear Ti(II) dinitrogen compound [(C5HMe4)2Ti]2N2 (8). Under a dynamic vacuum, the dinitrogen complex 8 loses the N2 ligand to give the titanocene (C5HMe4)2Ti (10). The molecular structures of both 4 and 8 were determined by X-ray diffraction methods.

Crystal structure of an isomeric bis[(η 5:η 1-6,6-di-p-tolylpentafulvene)(η 5-pentamethylcyclopentadienyl)titanium(III)]-μ 2,η 1:η 1-dinitrogen complex, C60H66N2Ti2

“…Besides many early transition metal complexes which are capable to activate and bind molecular nitrogen [5][6][7][8][9], our group reported the easy and smooth formation of dinuclear nitrogen-bridged low-valent titanium complexes [1]. These complexes appear to serve as synthons for di erent titanocenes, due to the weakly activated and displaceable dinitrogen.…”

Spectroscopic Comparison of Dinuclear Ti+ and Ti2+ μ‐η1:η1 Dinitrogen Complexes with Cp*/Pentafulvene and Amine/Amide Ligation: Moderate versus Strong Activation of N2

“…At first sight this observation appears to be contradictory. 1.160(3) [7] 2 1.160(5) [7] [{(η 5 -C 5 Me 5 ) 2 Ti} 2 (μ-η 1 :η 1 -N 2 )] 1.165(14) [8] [{(η 5 -C 5 Me 4 H) 2 Ti} 2 (μ-η 1 :η 1 -N 2 )] 1.170(4) [9] [{(η 5 -C 5 H 5 ) 2 Ti(PMe 3 )} 2 (μ-η 1 :η 1 -N 2 )] 1.191(8) [10] [{(η 5 -C 5 H 5 ) 2 Ti(p-tolyl)} 2 (μ-η 1 :η 1 -N 2 )] 1.162(12) [11] [{[η 5 1.289(9) [13] [{(Me 3 Si) 2 NTiCl(py) 2 } 2 (μ-η 1 :η 1 -N 2 )] 1.263(7) [14] [{[(Me 2 N)C(NiPr) 2 ] 2 Ti} 2 (μ-η 1 :η 1 -N 2 )] 1.280(8) [15] In order to address the above statement we investigated compounds 1, 2, and 3 with resonance Raman spec- Scheme 1. troscopy. The vibrational analysis was assisted by DFT calculations performed on structures I and III, which are models of complexes 1/2 and 3, respectively.…”

Synthesis and crystal structure of the singly tucked-in derivative of bis(phenyltetramethylcyclopentadienyl)titanium

“…Thermolysis of [Ti(III)Me(g 5 -C 5 HMe 4 ) 2 ] eliminated methane with exclusive formation of a paramagnetic dimer 2 (Scheme 2) [6], and thermolysis of [Ti(III)Me{g 5 -C 5 Me 4 (SiMe 3 )} 2 ] gave the silylmethylenetethered product 3 (Scheme 3) [7]. Thus, the below described unexpected formation of a singly tucked-in titanocene from thermolysis of the dimethyltitanocene [TiMe 2 (g 5 -C 5 Me 4 Ph) 2 ] (4) is so far the only case of obtaining a simple analogue of 1.…”