Investigation On The Synthesis Of Novel Tetrapyrrole Complexes And Their Properties

Tetrapyrrole is a total name of porphyrin,phthalocyanine,and their derivatives.They are important kinds of dyes and pigments with the significant potential applications,which share the same cyclic tetrapyrrole molecular framework.The complexation of the central N4 cavity of macrocycles with a large range of metal ions leads to the various kinds of coordination complexes with different molecular structure.Especially,with large eight-coordinated metal centers(e.g.lanthanides,actinides,and some main group elements),the complexes are either monomeric species with the metal ion out of the N4 plane or double-and triple-decker counterparts with the metal sandwiched between two neighboring tetrapyrrole ligands,the latter compounds can be called sandwich-type complexes.The typical molecular characters,including the free rotation of the adjacent macrocycles,the strong intramolecular ?-? interactions,multi-reversible and stable oxidation states,and ligand field with(‘4 symmetry as well as the ease in the chemical modification in the molecular structure,render these advanced molecular materials as proto-type molecule in the field of molecular machines,spectroscopy and electrochemistry.single-molecule magnets,chirality,field effect transistor,and liquid crystals.The below four topics are the main research contents:1 Design,Synthesis,and Single-Molecule Magnet of Novel Mixed(Porphyrin)(Schiff-Base)Dysprosium(?)Novel mixed(porphyrin)(Schiff-base)dysprosium(?)-potassium(?)complex[K(TBPP)Dy(L)(CH3CN)2][H2TTBPP =5.10,15.20-tetrakis(4-tert-butyl-phenyl)porphyrin:H2L =N,N'-bis(3-methyloxysalicylidene)benzene-1.2-diamine](1)was isolated from the reaction between metal free Schiff-base ligand of'N,N'-bis(3-methyloxysalicylidene)benzene-1.2-diamine(H2L)and half-sandwich porphyrinato dysprosium compound[Dy(TBPP)(acac)](Hacac = acetylacetone)in the presence of KOH.The sandwich-type double-decker structure has been unambiguously revealed on the basis of single crystal X-ray diffraction.The static and dynamic magnetic measurements disclosed the slow relaxation behavior of this new double-decker compound,indicating its SMM nature.Comparative studies on magnetic properties of 1 and homoleptic bis[5,10,15,20-tetrakis(4-tert-butyl-phenyl)porphyrinato]dysprosium double-decker in the form of[DyH(TBPP)2](2)and bis(Schiff-base)dysprosium double-decker {Dy[Zn(L)Cl]2(DMF)2]·Cl}(3)indicate the effect of the ligand field(LF),actually the deviation degree of the dysprosium coordination geometry from the ideal D4d form,on the SMM properties of 1-3,in addition to the effect of the charge distribution over Dy(III)ion.2 Mixed(Phthalocyanine)(Schiff-Base)Terbium(?)-Alkali Metal(?)/Zinc(?)Complexes.Synthesis,Structures,and Spectroscopic PropertiesA series of five mixed(phthalocyanine)(Schiff-base)terbium(?)-alkali metal(I)complexes Li(Pc)Tb(L)(CH3OH)2·(THF)(1)and M(Pc)Tb(L)(CH3OH)(M = Na,K,Rb,Cs)(2-5)have been synthesized and isolated from the reaction between metal free Schiff-base ligand of N.N'-bis(3-methyloxysalicylidene)benzene-1,2-diamine(H2L)and half-sandwich phthalocyaninato terbium compound M(Pc)(acac)(H2Pc = metal free phthalocyanine,Hacac = acetylacetone)with the help of corresponding alkali ion.The sandwich nature with mixed phthalocyanine and Schiff-base ligand of the whole series of five compounds has been unambiguously revealed on the basis of single crystal X-ray diffraction analysis.Electronic absorption and luminescence spectroscopic studies in particular the titration of 1-5 in mixed methanol/tetrahydrofuran with equivalent amount of Zn(?)ion leads to almost the same electronic absorption and luminescence spectra,suggesting the replacement of the alkali metal(I)ion locating at the 04 cavity of Schiff-base ligand by Zn(?)ion.This is confirmed by the X-ray diffraction analysis result for single cryrstals of novel mixed(phthalocyanine)(Schiff-base)terbium(?)-zinc(?)complex Zn(Pc)Tb(L)(Py)2(NO3)·(CH3OH)2·(THF)(6)obtained from the reaction of K(Pc)Tb(L)(CH3OH)(3)with excess amount of zinc nitrate in the presence of pyridine(Py).The present result will certainly attract interests for the design.synthesis,and further functional exploration of novel sandwich-type rare earth complexes involving tetrapyrrole and other macrocyclic ligands.3 Tetrakis(phthalocyaninato)Terbium-cadmium Quadruple-decker Liquid Crystals with Good Semiconducting PropertiesNeutral and mono-oxidized states of novel sandwich-type tetrakis[2,3,9,10,16,17,23,24-octa(dodecanoyloxy)phthalocyaninato]terbium-cadmium quadruple-decker complex{[Pc(OC12H25)8)]Tb[Pc(OC12H25)8]Cd[Pc(OC12H25)8]Tb[Pc(OC12H25)5]}(1)and{[Pc(OC12H25)8]Tb[Pc(OC12H25)8]Cd[Pc(OC12H25)8]Tb[Pc(OC12H25)8]}·SbCl6(2)were synthesized and spectroscopically characterized.Polarized optical microscope(POM)together with differential scanning calorimeter(DSC)measurement revealed their similar two rectangular columnar mesophases over a relatively lower temperature range and higher temperature range,respectively,within their wide liquid crystal temperature range of 19-266? for 1 and 4-249?for 2.Temperature-dependent X-ray diffraction(XRD)analysis result disclosed the slight difference in terms of the neighboring quadruple-decker ?-? stacking between these two mesophases,which in turn accounts for their electric conducting behavior along with the change in temperature.In addition,due to the ionic conductive nature,the mono-oxidized liquid crystals of 2 display more than 2 order of magnitude higher electric conductivity than that for 1,with the highest value 4.1 × 10-4 S cm-1 achieved at 140?.