New Coordination Complexes Based on the 2,6-bis[1-(Phenylimino)ethyl] Pyridine Ligand: Effective Catalysts for the Synthesis of Propylene Carbonates from Carbon Dioxide and Epoxides

作者：Xia, Li; Wang, Wen-Zhen^*; Liu, Shuang; Jia, Xin-Gang; Zhang, Ying-Hui; Li, Lei-Lei; Wu, Ya; Su, Bi-Yun; Geng, Shu-Bo; Fan, Wei

来源：Molecules, 2018, 23(9): 2304.

DOI：10.3390/molecules23092304

• coordination complexes
• carbon dioxide
• catalyst for propylene carbonate
• DFT calculations

We aimed to develop new effective catalysts for the synthesis of propylene carbonate from propylene oxide and carbon dioxide. A kind of Mx+LClx coordination complex was fabricated based on the chelating tridentate ligand 2,6-bis[1-(phenylimino)ethyl] pyridine (L). The obtained products were characterized by elemental analysis, infrared spectroscopy, ultraviolet spectroscopy, thermogravimetric analysis, and single-crystal X-ray diffraction. It was found that the catalytic activity of the complexes with different metal ions, the same ligand differed and co-catalyst, where the order of greatest to least catalytic activity was 2 > 3 > 1. The catalytic system composed of complex 2 and DMAP proved to have the better catalytic performance. The yields for complex 2 systems was 86.7% under the reaction conditions of 100 degrees C, 2.5 MPa, and 4 h. The TOF was 1026 h (1) under the reaction conditions of 200 degrees C, 2.5 MPa, and 1 h. We also explored the influence of time, pressure, temperature, and reaction substrate concentration on the catalytic reactions. A hypothetical catalytic reaction mechanism is proposed based on density functional theory (DFT) calculations and the catalytic reaction results.

• 出版日期2018-9
• 单位西安石油大学; 南开大学