Related Experiment Video
Updated: Aug 19, 2025
Controlled Photoredox Ring-Opening Polymerization of O-Carboxyanhydrides Mediated by Ni/Zn Complexes
Published on: November 21, 2017
Well-Defined and Highly Effective Nickel Catalysts Coordinated on Tridentate SNO Schiff-Base Derivatives for
Chen-Yen Tsai1, Min-Chia Huang2, Mei-Ling Lin1
1Department of Chemistry, Chinese Culture University, Taipei 111, Taiwan.
Abstract:
A series of Ni complexes supported by SNO Schiff-base derivatives were synthesized in this study. Complex synthesis and characterization data are reported herein. Treatment of the pro-ligands [L1-H = 2-(((2-(methylthio)ethyl)imino)methyl)phenol, L2-H = 2,4-di-tert-butyl-6-(((2-(methylthio)ethyl)imino)methyl)phenol, L3-H = 2-(((2-(methylthio)ethyl)imino)methyl)-4,6-bis(2-phenylpropan-2-yl)phenol, L4-H = 4-bromo-2-(((2-(methylthio)ethyl)imino)methyl)phenol, and L5-H = 4-chloro-2-(((2-(methylthio)ethyl)imino)methyl)phenol] with Ni(OAc)2·4H2O in refluxing ethanol afforded six-coordinate mono-Ni(II) complexes [L2Ni] (n = 1-5). Noteworthy, a heptanuclear nickel(II) octacarboxylate species complex 6 and dinuclear nickel complex 6a resulted from treatment of L6-H [4-fluoro-2-(((2-(methylthio)ethyl)imino)methyl)phenol] with different metal precursors [Ni(OAc)2·4H2O for 6; NiBr2 for 6a] giving a quantitative yield. The reaction of nickel acetate tetrahydrate and L7-H to L9-H [L7-H = 2-methoxy-6-(((2-(methylthio)ethyl)imino)methyl)phenol, L8-H = 5-methoxy-2-(((2-(methylthio)ethyl)imino)methyl)phenol, and L9-H = 4-methoxy-2-(((2-(methylthio)ethyl)imino)methyl)phenol] produced the four-coordinate complexes [L2Ni] (n = 7-9). The highest performing catalyst was complex 3, which was highly efficient for the ring-opening copolymerization of phthalic anhydride (PA) and cyclohexene oxide (CHO) in the presence of a cocatalyst (4-dimethylaminopyridine). In addition, the same copolymerization conditions produced narrowly dispersed polyesters, with high selectivity and polymerization control. In addition to PA-CHO copolymerization, efficient diglycolic anhydride-PA and PA-propene oxide copolymerization was achieved under the same conditions. These catalysts are straightforward to produce and extend the scope of potential substrates.
More Related Videos
08:13Chemical Precipitation Method for the Synthesis of Nb2O5 Modified Bulk Nickel Catalysts with High Specific Surface Area
Published on: February 19, 2018
09:08A Simple and Efficient Protocol for the Catalytic Insertion Polymerization of Functional Norbornenes
Published on: February 27, 2017
Related Concept Videos
02:57Sharpless Epoxidation
01:17Ziegler–Natta Chain-Growth Polymerization: Overview
02:24Acid-Catalyzed Ring-Opening of Epoxides
02:26Base-Catalyzed Ring-Opening of Epoxides
03:00Preparation of Epoxides
Epoxides result from alkene oxidation, which can be achieved by a) air, b) peroxy acids, c) hypochlorous acids, and d) halohydrin cyclization.
Epoxidation with Peroxy Acids
Epoxidation of alkenes via oxidation with peroxy acids involves the conversion of a carbon–carbon double bond to an epoxide using the oxidizing agent meta-chloroperoxybenzoic acid, commonly known as MCPBA. Since the O–O bond of peroxy acids is very weak, the addition of electrophilic oxygen of...
01:13Olefin Metathesis Polymerization: Overview
Ruthenium-based Grubbs catalyst is the most commonly used catalyst for olefin metathesis polymerization. Grubbs catalyst consists...