Homocoupling Reaction of Aryl Halides Catalyzed by Metal Cations in Isostructural Coordination Polymers
journal contributionposted on 03.08.2016, 00:00 by Li’an Guo, Chao Huang, Lu Liu, Zhichao Shao, Yue Tong, Hongwei Hou, Yaoting Fan
We have obtained a suite of two-dimensional layered isostructural coordination polymers [M(pypa)2(H2O)2]n (M = Mn (1), Co (2), Ni (3), Cu (4), respectively), Hpypa = 1H-[3-(4-pyridy)pyrazole]propionic acid), and used them in catalyzing the homocoupling of aromatic halides. 3 and 4 exhibit preeminent catalytic performance on the homocoupling of aryl bromide or aryl iodide without byproducts, while 2 only promoted the homocoupling of aryl iodide. But 1 showed no catalytic activities for all tested aromatic halides. Subsequently, density functional theory was performed for the balanced geometry frameworks, net charges of atoms, and energy of frontier molecule orbits. By using this method we determined that the catalytic performance was influenced by central metal ions. For further improving the catalytic performance, polyvinylpyrrolidone or polyethylene glycol 20000 (PEG 20000) was used as surfactants to synthesize the microscales of 3’s (3a and 3b). 3a and 3b showed more preeminent catalytic activity than 3.