Solvothermal Synthesis And Structural Characterization Of Novel Pyrazolated Copper(I)-Halide Complexes With Pyridyl Substituents

The design and synthesis of supramolecular coordination polymers featuring special structures is not only a hot topic, but also an important theme in coordination chemistry all along. However, the structures of complexes are controlled not only by the inherent characters of metals and ligands, but also by the reaction conditions. This work mainly focuses on the solvothermal syntheses and characterizations of series of new copper(I)-halide complexes containing pyridyl-pyrazolate ligands. Interestingly, during the syntheses of these novel complexes, some in situ reactions, such as metal redox reaction and N-alkylation reaction, have been founded and examined. The thesis is divided into three chapters.In Chapter 1, the research background of this work is concisely introduced with the emphasis on the current survey of in situ syntheses of metal complexes under hydro(solvo)thermal condtions and the copper(I) halides. The meaning and progress of this work have also been outlined.In Chapter 2, three pyrazole ligands with various substituents in the 3- or 5- position, namely 3-(3-pyridyl)-5-phenyl-pyrazole (L3–b), 3,5-bis(3-pyridyl)-pyrazole (L3–3), 3-(3-pyridyl)-5- (2-pyridyl)-pyrazole (L3–2), were synthesized. The reactions of L3–3 or L3–2 with copper halides under solvothermal or traditional conditions have been carried out and examined, yielding two polymeric copper(I) complexes, [Cu(bppz)I]n (1) and [Cu ((bppz-2)2] (2).In Chapter 3, ten new complexes (3-12) were obtained successfully under hydro(solvo)thermal conditions using L3–3 and L3–b as ligands, accompanying with halogens as counterion or bridging ligands. In these complexes, the coordination modes of ligands and copper(I) atoms are similar. The solvothermal reactions of bppz with CuBr2 in a molar ration of 1:2, 1:1 and 2:1 in methanol solution yielded a large amount of orange column crystals, namely [Cu2(DMbppz)Br3]2 (3), [Cu2(bppz)Br3]2 (4) and [Cu2(DMbppz)2Br2]n (5). Changing the solution with ethanol yielded [Cu3(DEbppz)Br4]n (6). Substituting ligand with pppz generate[Cu4(DM- Br -pppz)Br5]n (7), [Cu6(Mpppz)2Br8O]n (8) [Cu(pppz)Br]n (9) and [Cu3(Epppz)Br4]n (10). Interestingly, all the complexs except 5 and 9 contain neutral in situ N-alkylated ligands, which were obtained by increasing the amount of metal salts. On the other hand, the mechanism of the N-alkylation reaction is carefully studied, revealing that it is a simultaneous redox, N-alkylation and self-assembly reaction, and the R-Br has been considered as the key intermediate in the alkylated reaction. We obtained two other N-alkylated complexes Cu6(DMbppz) I8 (11) and [Cu ((bppz-2)2] (12)from copper(I) halides by enclosing oxidants.