220062-94-2Relevant academic research and scientific papers
Zirconium and hafnium complexes containing N-alkyl-substituted amine biphenolate ligands: Unexpected ligand degradation and divergent complex constitutions governed by N-alkyls
Liang, Lan-Chang,Chien, Chia-Cheng,Chen, Ming-Tsz,Lin, Sheng-Ta
, p. 7709 - 7716 (2013)
The reactivity and thermal stability of zirconium and hafnium complexes containing the N-alkyl-substituted amine biphenolate ligands of the type [RN(CH2-2-O-3,5-C6H2(tBu)2) 2]2- ([R-ONO]2-; R = tBu (1a), iPr (1b), or nPr (1c)) were investigated. The reactions of either [1a]M(OiPr)2 (M = Zr or Hf) with equimolar H2[1a] or M(OiPr)4(HOiPr) (M = Zr or Hf) with 2 equiv of H2[1a] at 25 C in diethyl ether or 80 C in toluene afford moderate yields of colorless crystals of M[1a](OiPr)(iPrOCH 2-2-O-3,5-C6H2(tBu)2) (M = Zr (4a) or Hf (5a)). Controlled experiments revealed that the production of 4a and 5a proceeds via unexpected thermal degradation of H2[1a] that produces a highly reactive, transient ortho-quinone methide intermediate. Similar reactions employing H2[1b] and H2[1c], however, led to the formation of homoleptic bis-ligand complexes Zr[1b]2 (8b) and M[1c]2 (M = Zr (8c) or Hf (9c)) as colorless crystals. Decisive factors governing these divergent reaction pathways and complex constitutions are discussed. The X-ray structures of 4a, 5a, 8b, 8c, and 9c are presented.
An unusual N-bridged (Amido)(hydrido)(phenoxido)aluminium dinuclear compound - The role of nitrogen substituents in determining nuclearity: A combined experimental and theoretical study
Martinez, Gema,Chirinos, Judith,Mosquera, Marta E. G.,Cuenca, Tomas,Gomez, Enrique
, p. 1522 - 1529 (2010/07/16)
Tho iminophonol 3,5-tBu2-2-(OH)C6H2CH=NR and the aminophonol 3,5-tBu2-2-(OH)C6H2CH 2-NHR (R = tBu, 2,6Me2C6H3, C 6F5) wore
Monocyclopentadienyl phenoxido-amino and phenoxido-amido titanium complexes: Synthesis, characterisation, and reactivity of asymmetric metal centre derivatives
Alesso, Giuseppe,Sanz, Martial,Mosquera, Marta E. G.,Cuenca, Tomas
experimental part, p. 4638 - 4649 (2009/03/12)
Reduction of phenol-imine derivatives R′N=CH(3,5-R2C 6H2-2-OH) (R = tBu; R′ = C6H5 1a, p-MeC6H4 1b, Cy 1c, tBu 1d, 2,6-Me2C 6H3 1e; R = H; R′ = p
