Reactivities And Structures Of Copper(Ⅰ) Salts And Flexible N-Heterocyclic Ligands

The coordination polymers derived from Cu(I) halides (Cl, Br, I) or pseudohalides (CN, SCN) and organic ligands have received much attention currently not only because of their structural diversities but also their potential applications as optical, adsorbent, and catalytic materials. Most of the architectures reported to date are based upon rigid ligands while only recent efforts are focused on the use of flexible ligands. In this thesis, we deliberately chose three kinds of flexible N-heterocyclic (benzimidazolyl-, benzotriazolyl- or 3,5-dimethyl-pyrazolyl-based) ligands with different spacer lengths and carried out their reactions with Cu(I)X (X = I, SCN, CN) at solvothermal conditions. 40 Cu(I) complexes were got by changing the flexibility of the ligands and the reaction conditions, which were briefly described as follows.1. Solvothermal reactions of CuI and flexible N-heterocyclic ligands with different spacer lengths afforded 13 new [CunIn]-based coordination polymers. The 3D framework of bulk CuI was cracked by the ligands into various [CunIn] motifs, such as mononuclear [CuI] in [(CuI)2(mbbm)2]n (2), [CuI(bbbm)1.5]n (5); dimeric [Cu2(μ-I)2] in [Cu2(μ-I)2L2]n (3: L = ebbm; 4: L = prbbm) and [Cu4(μ3-I)2(μ-CN)2(ebbt)]n (9); tetranuclear [Cu4(μ3-I)4] in [Cu4(μ3-I)4L]n (1: L = mbbm; 6: L = pbbm; 7: L = hbbm; 10: L = bbbt); 1D chain fragment in {[Cu3(μ3-I)3(ebbt)]}n (8) and [Cu2(μ3-I)2L]n (11: L = hbbt; 12: L = dmpzb) and mononuclear [CuI] and tetranuclear [Cu4(μ-I)2(μ3-I)2] in 13. These resulting units are further interconnected via ditopic flexible ligands to form new 1D chain or 2D networks. It is noted that structural diversities of these frameworks may be greatly affected by the flexible ligands and [CunIn] motifs while the CuI-to-ligand ratio, temperature and solvent systems may also worked. The photoluminescent properties of them were studied.2. Solvothermal reactions of bulk CuSCN and flexible N-heterocyclic ligands with different spacer lengths afforded a series of [CuSCN]n-supported coordination polymers. The 3D framework of bulk CuSCN was cracked by the ligands into four kinds of [CuSCN]n motifs. [(CuSCN)2L2]n (15: L = ebbm; 17: L = prbbm) consist of dimeric [CuSCN]2 fragment; [(CuSCN)2L]n (14: L = mbbm; 16: L = prbbm; 20: L = hbbm; 22: L = dmpzb) contain the 1D staircase-like [CuSCN]n chains; [(CuSCN)4(bbbm)3]n (18) consists of a rare [CuSCN]n double chain; [(CuSCN)2(pbbm)]n (19) and [CuSCN(prbbt)]n (21) consist of [CuSCN]n single chains. The structural diversities of these frameworks may be greatly affected by the flexible ligands and temperatures. The photoluminescent properties of 14-20 were studied.3. Solvothermal reactions of CuCN and flexible N-heterocyclic ligands with different spacer lengths afforded sixteen [CuCN]n-supported coordination polymers. [(CuCN)3L]n (23: L = dmpzm; 24: L = dmpze), [(CuCN)2L]n (25: L = dmpzpr; 26: L = dmpzb; 27: L = dmpzp; 28: L = dmpzh) were prepared by 3,5-dimethyl-pyrazole-based ligands; [(CuCN)2L]n (29: L = mbbm; 31: L = pbbm) and [(CuCN)3(ebbm)]n (30) were prepared by benzimidazolyl-based ligands; [(CuCN)4L]n (33: L = ebbt; 34: L = ebbt′;36: L = bbbt′), [(CuCN)2L]n (35: L = prbbt; 38: L = hbbt), [(CuCN)3(mbbt)]n (32) and [(CuCN)5(pbbt)]n (37) were prepared by benzotriazolyl-based ligands. They consist of similar 1D zigzag [CuCN]n chains, which were linked by flexible ligands with different spacer lengths to form 1D, 2D or 3D metal–organic frameworks. The photoluminescent properties of 23-28 were studied.4. We demonstrated one intriguing mixed-valence Cu(I,II) cyanide coordination polymer [Cu(II)Cu(I)2(μ-Br)2(μ-CN)2(bdmpp)]n (39) prepared from CuBr and bdmpp under solvothermal conditions. During the reaction, cyanide was assumed to be generated from the C-C bond cleavage of acetonitrile. Comparative reaction using CuCN and bdmpp gave rise to another Cu(I,II) cyanide coordination polymer [Cu(II)Cu(I)3(μ-CN)5(bdmpp)]n (40). The photoluminescent properties of 39-40 were also studied.