936741-84-3Relevant academic research and scientific papers
Structural characterization of a tetrametallic diamine-bis(phenolate) complex of lithium and synthesis of a related bismuth complex
Drover, Marcus W.,Murphy, Jennifer N.,Flogeras, Jenna C.,Schneider, Céline M.,Dawe, Louise N.,Kerton, Francesca M.
, p. 60 - 68 (2015)
A novel lithium complex was prepared from the reaction of 1,4-bis(2-hydroxy-3,5-di-tert-butyl-benzyl)imidazolidine H2[O2N2]BuBuIm (L1H2) with n-butyllithium to provide the corresponding tetralithium amine-bis(phenolate) complex {Li2[L1]}2·4THF, 1. Variable temperature 7Li NMR revealed that this complex is labile in solution, dissociating at elevated temperatures to afford two dilithium entities. Additionally, 7Li MAS NMR was performed on 1 to provide information regarding the lithium coordination environment in the bulk solid-state. The reactivity of 1 was assessed in the ring-expansion polymerization of ε-caprolactone (ε-CL), which was first order in ε-CL with an activation energy of 50.9 kJmol-1. Reaction of 1 and a related Li complex (formed in situ) with BiCl3 afforded hydrolytically unstable bismuth phenolate species, as evidenced by the isolation and structural characterization of [Bi4(Cl)3(μ-Cl)(μ-O)(O)2{[O2N2]BuBuPip}2], 2, where [O2N2]BuBuPip is the homopiperazine-containing analog of L1.
Structural characterization of dinuclear Ti(IV) complexes of rigid tetradentate dianionic diamine bis(phenolato) ligands; effect of steric bulk on coordination features
Manna, Cesar M.,Shavit, Michal,Tshuva, Edit Y.
, p. 3947 - 3950 (2008)
A small difference in diamine bis(phenolato) ligands, namely an additional single methylene unit, directs formation of dinuclear Ti(IV) complexes rather than mononuclear ones as characterized by X-ray crystallography. Varying steric bulk of the ligand affects the coordination number in the dinuclear complexes and the ligand to metal ratio. A ligand with reduced steric bulk leads to a L2Ti2(OiPr)4 type complex featuring two octahedral metal centers bridged only by the two phenolato ligands, whereas a bulky ligand leads to a Ti2(μ-L1)(μ-OiPr)2(OiPr)4 type complex with a single chelating ligand, two bridging isopropoxo ligands, and two terminal isopropoxo groups on each of the two metal centers, which are of trigonal bi-pyramidal geometry.
Synthesis and characterization of rare-earth metal guanidinates stabilized by amine-bridged bis(phenolate) ligands and their application in the controlled polymerization of rac-lactide and rac-β-butyrolactone
Zeng, Tinghua,Qian, Qinqin,Zhao, Bei,Yuan, Dan,Yao, Yingming,Shen, Qi
, p. 53161 - 53171 (2015/06/25)
Eight rare-earth metal guanidinates supported by a versatile family of chelating amine-bridged bis(phenolate) ligands were synthesized. Metathesis reactions of rare-earth metal chlorides [LnClL1(THF)] stabilized by amine-bridged bis(phenolate)
A highly active and stable imidazolidine-bridged N,O-donor ligand for efficient palladium catalyzed Suzuki-Miyaura reactions in water
Xue, Jun,Zhou, Zhonggao,Liu, Yulan,Huang, Li,Yu, Hongwei,Xie, Yongrong,Lai, Chen
experimental part, p. 331 - 335 (2012/08/07)
We have used the sterically hindered N,O-donor ligand 1,4-bis(2-hydroxy-3, 5-di-tert-butyl-benzyl)-imidazolidine with various Pd salts as a catalyst for the Suzuki reaction. This system exhibited excellent catalytic activity in Suzuki reactions of arylboronic acids with aryl halides, including aryl iodides, aryl bromides and activated aryl chlorides, using aqueous methanol as solvent under mild conditions. The catalytic system can be reused once without significant loss of activity. Graphical Abstract: The sterically hindered imidazolidine-bridged mixed nitrogen, oxygen ligand 1 was efficient for Pd-catalyzed Suzuki reactions involving aryl iodides, aryl bromides and activated aryl chlorides with arylboronic acid in aqueous methanol with K 2CO3 as a base the high catalytic activity and oxygen or moisture stable of palladium complexes maybe distribute to the bulky tert-butyl effect.[Figure not available: see fulltext.]
