Synthesis And Characteristics Of Porphyrin, Phthalocyanine And Helicenocyanine Metal Complexes

Owing to their unique optical, electrical, magnetic and other physical propertiesassociated with the intriguing inter-ring π-π interactions, sandwich-type porphyrinatoand/or phthalocyaninato metal complexes have been intensively investigated overseveral decades as prospective molecular electronic conductors, molecular magnetic,and non-linear optical materials.Four new mixed rare earth triple-decker complexes M2(TPyP)(TBPc)2(M=Ce,Sm, Tb and Tm) have been prepared by treating M(acac)(TPyP) with correspondinghomoleptic substituted bis(phthalocyaninato) rare earth complexes M(TBPc)2inrefluxing1,2,4-trichlorobenzene (TCB), typical for the light, middle, and heavy rareearths, respectively. Typical IR marker bands of the substituted phthalocyaninedianion Pc(TBPc)2-show strong bands at ca.1323cm-1, and are attributed to pyrroleC=C stretchings. The TPyP-IR marker band at ca.1270-1300cm-1was not observedfor these compounds. A very strong band at1500cm-1with contributions from bothpyrrole C=C and aza C=N stretchings and also isoindole stretching was the markerRaman band of (TBPc)2-. Their electrochemical properties were investigated by cyclicvoltammetry (CV) and differential pulse voltammetry (DPV). The four complexeswere also characterized by EA, MS and UV-vis spectra.Raman spectroscopic data in the range of500-1800cm-1for a series of ninemixed rare earth triple-deckers M2[TO(OH)PP](Pc)2(M=La...Dy, except Pm) havebeen collected using laser excitation sources emitting at632.8nm. Comparison withthe Raman spectra of the corresponding bis(phthalocyaninato) and mixeddouble-decker rare earths reveals that the Raman characteristics of these mixedtriple-deckers M2III[TO(OH)PP](Pc)2are dominated by Pc2-contributions. There is noobvious band that can be assigned to the [TO(OH)PP]2-moiety. Under excitation at632.8nm, typical Raman marker bands of the phthalocyanine dianions Pc2-wereobserved at1514-1526cm-1as medium band, resulting from the coupling of pyrroleC=C and aza C=N stretchings. For Ce2[TO(OH)PP](Pc)2, a strong band at1521cm-1with contribution from both pyrrole C=C and aza C=N stretches as well as theisoindole stretches was the marker Raman band of Pc2-. The Raman spectra of thesemixed triple-decker complexes reveal that most of the Raman vibrations derived from pyrrole stretching, isoindole breathing, C–H bend and aza stretching are decreasedsensitive to the rare earth ionic size, and remain basically unchanged along with thelanthanide contraction. These facts indicate that the π-π interactions in these mixedtriple-deckers are weaker than those in the double-deckers.Novel heteroleptic double-decker rare earth complexes PcM(HcR8)(M=Pr, Nd,Sm, Eu)(R=OMe, OC8H17), metal free and transition metal complexesMHc(OC8H17)8(M=HH, Fe, Co, Ni, Cu) have been synthesized. These complexeswere characterized by IR, MS and UV-vis spectra. They have good solubility incommon organic solvents. The electronic absorptions of MHc(OC8H17)8(M=HH, Fe,Co, Ni, Cu) are obviously red shifted compared with the related phthalocyanincomplexes. However the synthesis and purification of heteroleptic double-decker rareearth complexes PcM(HcR8)(M=Pr, Nd, Sm, Eu)(R=OMe, OC8H17) are moredifficult than those in the related porphyrinato-phthalocyaninato complexes.