Studies On Reactivities Of 1,2,3,4-tetra(pyridin-4-yl)cyclobutane And Cu(?) Salts

Mental-organic frameworks(MOFs)have attracted much attention recently because of their intriguing topologies structural and potential applications in photology,magnetism,catalysis,adsorption,and gas storage.In this dissertation,we prepare a series of Cu(I)-MOFs by self-assembly of copper(I)halide or pseudohalide with tetrakis(4-pyridyl)cyclobutane(tpcb)under the solvothermal conditions and examine their luminescent properties and in situ cycloreversion of tpcb.These results are briefly described as follows:1.The reactions of Cu(I)halides(Cl,Br,I)or pseudohalides(CN,SCN)with tetrakis(4-pyridyl)cyclobutane(tpcb)under solvothermal conditions result in the formation of five Cu(I)-MOFs,formulated as {[Cu2Cl2(tpcb)1.5]·5H2O}n(1),[Cu Br(tpcb)0.5]n(2),[Cu2I2(tpcb)2]n(3),{[Cu3(?-CN)3(tpcb)]·2DMF}n(4)and [Cu2(?-SCN)2(tpcb)0.5]n(5).In 1-5,mononuclear [Cu Cl](1),dimeric [Cu2X2](X = Br,I,SCN)(2,3,5)and 1D chain [Cu3(?-CN)3]n(4)fragments are linked by tpcb to form various 3D networks.2 exhibits a fluorescent emission peak at 467 nm upon excitation at 420 nm.Their energy gaps are less than 3.0 e V,indicating that they could be used as semiconducting materials.2.Solvothermal reaction of Cu CN with tpcb affords a MOF [Cu7(?-CN)7(tpcb)2]n(6).The addition of HCl yields another MOF {[Cu4(?-CN)4(tpyf)]·4CH3CN}n(7,tpyf = 2,3,4,5-tetra(4-pyridyl)furan).In this reaction,tpcb is converted into furan-based tpyf ligand.In the presence of 2,2,6,6-tetramethylpiperidine-1-oxyl(TEMPO),solvothermal reactions of Cu CN with tpcb at 160 oC produced {[Cu18(?-CN)18(tpcb)4(tpyb)2]·H2O}n(8,tpyb = 1,2,3,4-tetra(4-pyridyl)-1,3-butadiene).The tpcb ligand undergoes the thermal cleavage of one C-C bond into the radical species,which was then captured by O2 to form tpyf,or might be catched by TEMPO to form a distorted 1,3-butadiene product tpyb.It is anticipated that the methodology using suitable [Cun Xn]-supported MOFs to trap the cleaved species and regain some delicate mechanism information would be could be applied to other relevant C-Y(Y = C,N,O,P,S,Si)cleavage systems under solvothermal conditions.