Synthesis,Transformation And Mechanical Catalysis Of Binuclear Cu(Ⅱ) Complexes And Metal-Organic Salts In Solid State

Complexes and metal-organic salts are two different kinds of organometallic compounds:complexes connect ligands to metals through coordination bonds,while metal-organic salts are connected between organic ligand cations and transition metal complex anions through intermolecular interaction forces.With their structural diversity and functional tunability,organometallic compounds have a wide range of applications and development prospects in scientific fields such as catalysis,medicine,luminescence,and inorganic materials.Mechanochemistry has many advantages in terms of improved reactivity,higher reaction yields,reduced environmental impact,and reactions under mild and solvent-free conditions,making it an effective alternative to green synthetic chemistry with a wide range of applications in organic synthesis,catalysis,and synthesis of metal complexes.In this thesis,we use mechanochemistry as the main research method to synthesize ligands step by step,prepare dinuclear complexes and their metal-organic salts,and further investigate the catalytic C-S cross-coupling reactions under mechanical forces.The details are as follows.1.3-benzyl-1-（pyridin-2-ylmethyl）benzoimidazolium salt ligand L.PF₆ was synthesized step by step using a ball mill under solvent-free conditions;subsequently,the ligand L.PF₆ was synthesized with Cu Cl₂·2H₂O by liquid-assisted grinding of the complex[Cu L（μ-Cl）Cl₂]₂（1）and the metal-organic salt[H₂L]²⁺·[Cu Cl₄]^2-（2）.The above compounds were characterized and analyzed using infrared spectroscopy,nuclear magnetic ¹H NMR,X-ray powder diffractometer,and X-ray single-crystal diffractometer.2.The solid-state reversible conversion between the complexes and metal organic salts was investigated.The results show that complex 1 adsorbs HCl molecules by solid-gas reaction,which breaks the coordination bonds and forms new Cu-Cl and N-H bonds to obtain metal-organic salt 2.Metal-organic salt 2 is ground with strong base t-Bu OK to generate HCl by shedding Cl^-from complex anion[Cu Cl₄]^2-and H⁺from[HL]²⁺to obtain the corresponding complex 1.3.Complex 1 and metal-organic salt 2 were applied as transition metal catalysts in mechanically catalyzed C-S cross-coupling reactions.The findings revealed that the catalytic activity of complex 1 was superior among the tested compounds,and the optimal reaction conditions were optimized for the catalytic conditions:1.0 mol%of complex 1 as catalyst catalytic conditions,60μL of methanol as a liquid auxiliary grinding agent,and the reaction was carried out at 30 Hz for 20 min to achieve 96%yield.The system showed good substrate compatibility when applied to different substrates.Mechanochemistry was also applied to the functional group transformation of compound 3a,yielding ketoxime 4a.In general,this paper utilizes mechanochemical ball milling technique to synthesize a series of metal-organic compounds as catalysts and applies them in C-S cross-coupling reactions.This expands the application of mechanochemistry in organic reactions,representing a general approach in this paper.