150255-48-4Relevant academic research and scientific papers
Synthesis of nickel and palladium complexes with diarylamido-based unsymmetrical pincer ligands and application for norbornene polymerization
Liu, Hui,Yuan, Haibin,Shi, Xiaochao
, p. 609 - 617 (2019/01/08)
A set of diarylamido-based unsymmetrical [PNNox] pincer ligands containing a chiral oxazoline ring have been synthesized and their nickel and palladium complexes [(2-PPh2(R1)ArN(R1)Ar-2-(R)oxazoline)MCl] (R1 = 4-H, R = (S)-4-iPr, M = Pd (Pd1); R1 = 4-H, R = (S)-4-Bn, M = Pd (Pd2); R1 = 4-H, R = (S)-4-Ph, M = Pd (Pd3); R1 = 4-Me, R = (S)-4-Bn, M = Pd (Pd4); R1 = 4-Me, R = (S)-4-Ph, M = Pd (Pd5); R1 = 4-H, R = 4-Me2, M = Pd (Pd6); R1 = 4-H, R = Benzo[d]-, M = Pd (Pd7); R1 = 4-H, R = (S)-4-Bn, M = Ni (Ni1); R1 = 4-H, R = (S)-4-Ph, M = Ni (Ni2); R1 = 4-Me, R = (S)-4-Bn, M = Ni (Ni3); R1 = 4-Me, R = (S)-4-Ph, M = Pd (Ni4)) were tested to show high catalytic activities for polymerization of norbornene. After activation of methylaluminoxane (MAO), all the nickel and palladium complexes could catalyze the polymerization of norbornene to yield vinyl-type polymers with activities up to 40.3 × 105 g of PNB (mol of Pd)?1 h?1. The copolymerization of norbornene with functional norbornene comonomers was also investigated by catalyst Pd2, accompanied by decreased catalytic activity and low incorporation of functional comonomers.
Nickel(II) complexes bearing phosphinooxazoline ligands: Synthesis, structures and their ethylene oligomerization behaviors
Tang, Xiubo,Zhang, Dongheng,Jie, Suyun,Sun, Wen-Hua,Chen, Jiutong
, p. 3918 - 3928 (2007/10/03)
A series of Ni(II) complexes 4a-f ligated by the unsymmetrical phosphino-oxazolines (PHOX) were synthesized and characterized by elemental analysis and IR spectroscopy, and the structures of complexes 4c-4e were confirmed by the X-ray crystallographic analysis. All derivatives showed distorted tetrahedron geometry by the nickel center and coordinative atoms. Upon activation with methylaluminoxane (MAO) or Et2AlCl, these complexes exhibited considerable to high activity of ethylene oligomerization. The ligands environments and reaction conditions significantly affect their catalytic activities, while the highest oligomerization activity (up to 1.18 × 106 g ? mol-1(Ni) ? h-1) was observed for 4d at 20 atm of ethylene. Incorporation of 2-4 equivalents of PPh 3 as auxiliary ligands in the 4a-f/MAO catalytic systems led to higher activity and longer catalytic lifetime.
Palladium-catalysed Asymmetric Allylic Substitution: a Ligand Design Incorporating Steric and Electronic Effects
Allen, Joanne V.,Coote, Steven J.,Dawson, Graham J.,Frost, Christopher G.,Martin, Christopher J.,Williams, Jonathon, M.
, p. 2065 - 2072 (2007/10/02)
Enantiomerically pure ligands containing a 4,5-dihydrooxazole moiety tethered to an auxiliary sulfur or phosphorus donor have been prepared.These ligands have been exploited for palladium-catalysed asymmetric allylic substitution, providing enantioselectivity in the catalytic reaction is discussed in terms of the steric and electronic influences provided by the ligand.
Preparation of Novel Sulfur and Phosphorus Containing Oxazolines as Ligands for Asymmetric Catalysis
Allen, Joanne V.,Dawson, Graham J.,Frost, Christopher G.,Williams, Jonathan M. J.,Coote, Steven J.
, p. 799 - 808 (2007/10/02)
The preparation of enantiomerically pure ligands which contain both an oxazoline group and an additional sulfur or phosphorus donor atom are described.Methylthiomethyl, o-thioanisyl and thienyl oxazolines have been prepared in one step, and o-diphenylphosphinophenyl oxazolines have been prepared in two steps in good yields from commercially available starting materials.
Asymmetric Palladium Catalysed Allylic Substitution Using Phosphorus Containing Oxazoline Ligands
Dawson, Graham J.,Frost, Christopher G.,Williams, Jonathan M. J.,Coote, Steven J.
, p. 3149 - 3150 (2007/10/02)
A series of new phosphorus-containing oxazoline ligands has been developed.The use of these ligands for asymmetric palladium catalysed allylic substitution of 1,3-diphenylprop-2-enyl-1-acetate 12 with the sodium salt of dimethylmalonate has been achieved
