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1.
A novel approach to heteroleptic heteronuclear rare earth metal(III) trisphthalocyaninates was proposed with the complexes [(15C5)4Pc]M*[(15C5)4Pc]M(Pc) as examples (15C5 is 15-crown-5, Pc2? is the phthalocyaninate dianion, and M* ?? M = Yb and Y). Unsubstituted lanthanum bisphthalocyaninate, La(Pc)2, was used for the first time as a Pc2? donor in the synthesis of such complexes. This substantially increased the yields of the target heteronuclear complexes over the previous literature data.  相似文献   

2.
A series of heteroleptic bis(phthalocyaninato) europium(III) complexes, namely, Eu(Pc)[Pc(15C5)] (2), Eu(Pc)[Pc(opp-15C5)2] (3), Eu(Pc)[Pc(adj-15C5)2] (4), Eu(Pc)[Pc(15C5)3] (5), and Eu(Pc)[Pc(15C5)4] (6) [Pc = unsubstituted phthalocyaninate; Pc(15C5) = 2,3-(15-crown-5)phthalocyaninate; Pc(opp-15C5)2 = 2,3,16,17-bis(15-crown-5)phthalocyaninate; Pc(adj-15C5)2 = 2,3,9,10-bis(15-crown-5)phthalocyaninate; Pc(15C5)3 = 2,3,9,10,16,17-tris(15-crown-5)phthalocyaninate, Pc(15C5)4 = 2,3,9,10,16,17,24,25-tetrakis(15-crown-5)phthalocyaninate], with one, two, three, and four 15-crown-5 voids attached at different positions of one of the two phthalocyaninato ligands in the double-decker molecules, have been devised and prepared by Eu(Pc)(acac)-induced (Hacac = acetylacetone) mixed cyclization of the two corresponding phthalonitriles in the presence of organic base 1,8-diazabicyclo[5.4.0]undec-7-ene (DBU) in n-pentanol. For the purpose of comparative studies, homoleptic counterparts Eu(Pc)2 (1) and Eu[Pc(15C5)4]2 (7) have also been prepared. These sandwich double-decker complexes have been characterized by a wide range of spectroscopic methods in addition to elemental analysis. Their electrochemistry has also been studied by cyclic voltammetry (CV) and differential pulse voltammetry (DPV). The molecular structure of Eu(Pc)[Pc(15C5)4] (6) has been determined by X-ray diffraction analysis. Their supramolecular structure-formation properties, in particular for compounds 5 and 6 in the presence of potassium ions, have also been comparatively studied for the purpose of future functional investigation.  相似文献   

3.
A novel approach for the structural analysis of heteroleptic triple‐decker (porphyrinato)(phthalocyaninato) lanthanides(III) in solutions is developed. The developed approach consists in molecular mechanics (MM+) optimization of the geometry of the complex taking into account the lanthanide‐induced shift (LIS) datasets. LISs of the resonance peaks in 1H NMR spectra of a series of symmetric complexes [An4P]Ln[(15C5)4Pc]Ln[An4P], where An4P2? is 5,10,15,20‐tetrakis(4‐methoxyphenyl)porphyrinato‐dianion, [(15C5)4Pc]2? is 2,3,9,10,16,17,24,25‐tetrakis(15‐crown‐5)phthalocyaninato‐dianion and Ln = La, Ce, Pr, Nd, Sm, Eu, are analyzed. Analysis of LISs showed two sets of protons in the molecule with opposite signs of shift. Two‐nuclei analysis of LISs testifies isostructurality of the whole series of investigated complexes in solution despite contraction of the lanthanide ions. Model‐free separation of contact and dipolar contributions of LISs was performed with one‐nucleus technique and did not show changes in contact and dipolar terms within the investigated series. MM+ optimization of the molecular structure allowed the interpretation of features of LIS for each particular group of protons. Parameterization of MM + ‐optimized model of molecule with values of structure‐dependent dipolar contributions of LIS allows the development of the precise structural model of the triple‐decker complex in solution. This approach allows the determination of the geometry and structure of the sandwich macrocyclic tetrapyrrolic complexes together with conformational analysis of flexible peripheral substituents in solutions. The developed method can be applied with minor modifications for the determination of structural parameters of other types of lanthanides(III) complexes with tetrapyrrolic ligands and also supramolecular systems based on them. Copyright © 2010 John Wiley & Sons, Ltd.  相似文献   

4.
An effective one-step approach for the preparation of (porphyrinato)(phthalocyaninato) early lanthanides of type [Br(4)TPP]Ln[(15C5)(4)Pc]Ln[Br(4)TPP], where Br(4)TPP = 5,10,15,20-tetrakis-(4-bromophenyl)-porphyrinato-ligand, (15C5)(4)Pc = tetrakis-(15-crown-5)-phthalocyaninato-ligand and Ln = La, Pr, Nd or Eu, is developed. The influence of various factors on the reaction pathway and yields of the complexes is investigated in detail. The developed protocol is found to be general for the early lanthanide subgroup. Variation of the synthetic conditions allowed the determination and isolation of possible side-products, namely heteroleptic double-deckers [Br(4)TPP]Ln[(15C5)(4)Pc] (Ln = Nd, Eu) and triple-decker [Br(4)TPP]Nd[(15C5)(4)Pc]Nd[(15C5)(4)Pc]. The peculiarities of the NMR lanthanide-induced shifts (LIS) of resonances of the synthesized triple-decker complexes are precisely investigated. The isostructurality of the synthesized complexes within the series as well as isostructurality with previously synthesized compounds is demonstrated in terms of two-nuclei analysis of LIS.  相似文献   

5.
Erbium mono-, bis-, and tris(phthalocyaninates) with tetra-15-crown-5-phthalocyanine (H2R4Pc) were synthesized and studied by spectroscopic methods. The complexes were obtained by reacting H2R4Pc with erbium salts in high-boiling solvents. To compare the efficiency of two approaches to the synthesis of double-decker lanthanide phthalocyaninates, bis(phthalocyaninate) [Er(R4Pc)2] was also obtained by a template procedure from dicyanobenzo-15-crown-5. A combination of physicochemical methods (UV and IR spectroscopy, MALDI-TOF mass spectrometry, 1H NMR) was used for identifying the compounds and proving their individuality and structure. The photoluminescence method demonstrated that solutions of erbium bis- and tris(phthalocyaninates) in CHCl3 are nonfluorescent in the visible range of light whereas solutions of mono(phthalocyaninate) in CHCl3 and DMSO exhibit fluorescence with maxima at 707 and 695 nm, respectively. The oxidation of erbium mono(phthalocyaninate) leads to fluorescence quenching.  相似文献   

6.
Intramolecular dynamics of meso-aryl substituents of porphyrin deck in the triple-decker lanthanide (porphyrinato)(phthalocyaninates) of symmetrical type [Br(4)TPP]Ln[(15C5)(4)Pc]Ln[Br(4)TPP] (Ln = La, Nd, Eu; [Br(4)TPP] = tetrakis-5,10,15,20-(4-bromophenyl)-porphyrinato-ligand; [(15C5)(4)Pc] = tetrakis-(15-crown-5)-phthalocyaninato-ligand) are investigated. Attempts to achieve coalescence were not successful, although the trend of exchanging protons to coalescence point was observed in the case of Nd and Eu complexes. The analysis of NOESY cross-peaks between exchanging protons allowed to evaluate the rotation rate constants at different temperatures. The activation barrier of the meso-aryl substituent rotation was calculated with Arrhenius equation based on determined rate constants. The rate constants are lower and activation barriers are higher than ones found previously for related compounds.  相似文献   

7.
Electronic absorption spectroscopy and fluorimetry have been employed to study the behavior of magnesium octa[(4′-benzo-15-crown-5)oxy]phthalocyaninate (Mg[(B15C5O)8Pc]) in aqueous micellar solutions of sodium dodecyl sulfate and hexadecyltriphenylphosphonium bromide. Conditions have been found for the existence of monomeric Mg[(B15C5O)8Pc] complex in surfactant solutions to provide the possibility of using mixed solutions of the complex and cationic surfactants (alkyltriphenylphosphonium bromides) for photodynamic therapy. In surfactant solutions with different concentrations of micelles (cm) and the complex (cp), the maximum amount of monomeric Mg[(B15C5O)8Pc] is achieved at cm/cp ≥ 4.  相似文献   

8.
Three novel equations were proposed to perform graphical model-free analysis of lanthanide-induced shifts in NMR spectra of axially symmetrical complexes within Bleaney's T(-2) expansion. Application and efficiency of these newly developed approaches were demonstrated on the example of heteroleptic triple-decker crown-phthalocyaninates (Pc)M[(15C5)(4)Pc]M(Pc), where (15C5)--15-crown-5, (Pc(2-))--phthalocyaninato-dianion, M = Nd, Sm, Eu, Tb, Dy, Ho, Er, Tm, Yb and Y as diamagnetic reference. By construction of these equations, the proposed analytical techniques are more sensitive to variations of hyperfine coupling terms throughout lanthanide series, in comparison with previously developed approaches, becoming a valuable tool for the investigation of structural and electronic characteristics of lanthanide complexes.  相似文献   

9.
Praseodymium(III) complexes with tetra-15-crown-5-phthalocyanine—the neutral radical [(R4Pc)Pr3+(R4Pc2?)]0 and one-electron reduced [(R4Pc2?)Pr3+(R4Pc2?)]? forms of the sandwich double-decker complex and the triple-decker complex Pr2(R4Pc)3 (R4Pc2? is [4,5,4′,5′,4″,5t",4″′,5″′-tetrakis(1,4,7,10,13-pentaoxatridecamethylene)phthalocyaninate ion])—have been synthesized and spectrally characterized. These compounds have been obtained by direct interaction of tetra-15-crown-5-phthalocyanine with praseodymium(III) acetate or acetylacetonate. The salt anion has an effect on the yield and structure of the reaction products. The complexes have been obtained in high yields, isolated, and characterized by different physicochemical methods: UV and visible electronic absorption spectroscopy, 1H NMR, and MALDI-TOF mass spectrometry. The double-decker complex is stable in the solid state and in solutions. The triple-decker complex is stable only in the solid state. In a chloroform-methanol (10 vol %) solution, it slowly decomposes.  相似文献   

10.
New heteroleptic triple-decker terbium complexes of general structure [Br(4)TPP]Tb[(15C5)(4)Pc]Tb[Br(4)TPP] (Tb-TD) and [Br(4)TPP]Tb[(15C5)(4)Pc]Tb[(15C5)(4)Pc] (Tb-TD*) (Br(4)TPP = tetrakis-meso-(4-bromophenyl)-porphyrin, (15C5)(4)Pc = tetra-(15-crown-5)-phthalocyanine) are synthesized with 48% and 57% yields, respectively. The triple-decker complexes were prepared by interaction of generated in situ terbium monoporphyrinate [Br(4)TPP]Tb(acac) and corresponding double-decker precursors. The heteroleptic double-decker precursor [Br(4)TPP]Tb[(15C5)(4)Pc] was prepared for the first time in a two step one-pot synthesis. No ligand scrambling was observed in the synthesis of Tb-TD, while 4% scrambling was determined in the case of Tb-TD*. High yields of target triple-decker complexes were achieved despite the presence of electron-donating crown-ether fragments with low thermal stability at the phthalocyanine deck. Analysis of lanthanide-induced paramagnetic shifts of protons of Tb-TD together with data of previously reported La, Pr, Nd and Eu analogues allowed precise separation of contributions of contact and dipolar lanthanide terms as well as verification of isostructurality of complexes within the series.  相似文献   

11.
The reductive reactivity of lanthanide hydride ligands in the [(C5Me5)2LnH]x complexes (Ln = Sm, La, Y) was examined to see if these hydride ligands would react like the actinide hydrides in [(C5Me5)2AnH2]2 (An = U, Th) and [(C5Me5)2UH]2. Each lanthanide hydride complex reduces PhSSPh to make [(C5Me5)2Ln(mu-SPh)]2 in approximately 90% yield. [(C5Me5)2SmH]2 reduces phenazine and anthracene to make [(C5Me5)2Sm]2(mu-eta(3):eta(3)-C12H8N2) and [(C5Me5)2Sm]2(mu-eta(3):eta(3)-C10H14), respectively, but the analogous [(C5Me5)2LaH]x and [(C5Me5)2YH]2 reactions are more complicated. All three lanthanide hydrides reduce C8H8 to make (C5Me5)Ln(C8H8) and (C5Me5)3Ln, a reaction that constitutes another synthetic route to (C5Me5)3Ln complexes. In the reaction of [(C5Me5)2YH]2 with C8H8, two unusual byproducts are obtained. In benzene, a (C5Me5)Y[(eta(5)-C5Me4CH2-C5Me4CH2-eta(3))] complex forms in which two (C5Me5)(1-) rings are linked to make a new type of ansa-allyl-cyclopentadienyl dianion that binds as a pentahapto-trihapto chelate. In cyclohexane, a (C5Me5)2Y(mu-eta(8):eta(1)-C8H7)Y(C5Me5) complex forms in which a (C8H8)(2-) ring is metalated to form a bridging (C8H7)(3-) trianion.  相似文献   

12.
The unusual formation of planar trimethylenemethane (TMM) dianion complexes of lanthanide metallocenes, [(C5Me5)2Ln]2[mu-eta3:eta3-C(CH2)3] (Ln = Sm, 1; La, 2; Pr, 3; Nd, 4; Y, 5) has been examined by synthesizing examples with metals from La to Y to examine the effects of radial size on structure and to provide closed shell examples for direct comparison with density functional theory (DFT) calculations. Synthetic routes to 1-4 have been expanded from the [(C5Me5)2Ln][(mu-Ph)2BPh2]/neopentyl lithium reaction involving beta-methyl elimination to a [(C5Me5)2Ln][(mu-Ph)2BPh2]/isobutyl lithium route. The synthetic pathways are sensitive to metal radius. To obtain 5, the methylallyl complex, (C5Me5)2Y[CH2C(Me)CH2], 6, was synthesized and treated with [(C5Me5)2YH]x. In the Lu case, the neopentyl complex [(C5Me5)2LuCH2C(CH3)3]x, 7, was isolated instead of the TMM product. X-ray crystallography showed that the metrical parameters of the planar TMM dianions in each complex are similar. The structural data have been compared with DFT calculations on the closed-shell lanthanum and lutetium complexes that suggest only limited covalent interactions with the lanthanide ion. Benzophenone (2 equiv) reacts with 1 to expand the original four-carbon TMM skeleton to a dianionic bis(alkoxide) ligand containing a symmetrically substituted C=CH2 moiety in [(C5Me5)2Sm]2[mu-(OCPh2CH2)2C=CH2], 8. In this reaction, the TMM complex reacts as a bifunctional bisallylic reagent that generates an organic framework containing a central vinyl group.  相似文献   

13.
The cation-induced aggregation of sandwich crown-substituted complexes [Ln(R4Pc)2] (Ln = Lu (I) and Yb (II), R4Pc2? is the 4,5,4′,5′,4″,5″,4?,5?-tetrakis(1,4,7,10,13-pentaoxatridecamethylene)phthalocyaninate ion) and Ln2(R4Pc)3(Ln = Lu (III) and Yb (IV) in a CDCl3-DMSO-d 6 solution has been studied by 1H NMR. The data obtained are consistent with the conclusions concerning the composition of supramolecular aggregates drawn from spectrophotometric titration data. The molecules of double-decker complexes I and II form supramolecular oligomers, whereas triple-decker complexes III and IV form supramolecular dimers, which is presumably due to the stronger distortion of the planes of the outer decks of the triple-decker complexes as compared to their double-decker analogues.  相似文献   

14.
The photoelectric sensitivity and photorefractive properties at 1064 nm of composites consisting of poly(vinyl carbazole) (PVC), complexes of ruthenium(II) with tetra-15-crown-5-phthalocyanine and axially coordinated CO and CH3OH molecules (R4Pc)Ru(CO)(CH3OH), R4Pc2? is tetrakis-(1,4,7,10,13-pentaoxatridecamethylene)phthalocyaninate ion in the presence and absence of ferrocene were studied. The nature of the optical absorption within the near IR region in composites prepared from PVC and (R4Pc)Ru(TED)2 (TED is triethylenediamine) and (R4Pc)Ru(CO)(CH3OH) is discussed. It was established that the photoelectric, non-linear optical, and photorefractive properties of the polymer composite are determined by supramolecular ensemble composed of Ru(II) crown-phthalocyanines.  相似文献   

15.
It is established that supramolecular ensembles on the basis of the complex of ruthenium(II) with tetra-15-crown-5-phthalocyanine and axially coordinated triethylenediamine molecules (R4Pc)Ru(TED)2, where R4Pc2? and TED denote 4,5,4′,5′,4″,5″4?,5?-tetraksis-(1,4,7,10,13-pentaoxatridecamethylene)phthalocyaninate ion and triethylenediamine molecule, respectively) make an aromatic polyamide layer photoelectrically sensitive to 1064-nm Nd:YAG laser radiation, exhibit third-order susceptibility, and, consequently, impart photorefractive properties to the polymer layer at this wavelength.  相似文献   

16.
Complexes between the heavier lanthanoid nitrates Ln(NO3)3 and 15-crown-5 ( 1 ) and 18-crown-6 ( 2 ) ethers were isolated and characterized. Both 1:1 and 4:3 complexes are formed with each Ln(III) ion, except in the case of Gd and 2 . The thermal transformation of the 1:1 complexes into the corresponding 4:3 complexes was studied by thermogravimetry and by DSC, X-ray and vibrational data provide information about the structure of these complexes. The interaction between Ln(III) ions and ligands 1 and 2 in non-aqueous solutions is discussed on the basis of conductometric, fluorescence, UV./VIS. and 1H-NMR. data. Only 1:1 complexes of 2 formed in solution and their formation constants range from logKf = 4.4 (Ln = La) to 2.4 (Ln = Yb); for Eu, Kf of the 15-crown-5 and 18-crown-6 ether complexes are of the same order of magnitude. For La, Pr, Nd, Eu, Yb, a variable temperature NMR. study gave some indications about the chemical exchanges in solution. The factors which determine the stoichiometry of the complexes are discussed.  相似文献   

17.
The selectivity factor in the separation of lanthanide could be associated with the coordination behaviour. Thus, we observed the study in the solid phase to understand the coordination pattern of Ln(III) with the 18-crown-6 (18C6) ligand. Good selectivity of the rigid 18C6 ligand toward Ln(III) depends on gradually smaller their ionic radii of Ln(III) in the complexes formation in the presence of picrate anion (Pic), i.e. lanthanide contraction and steric effects as clearly shown in the series of [Ln(Pic)2(18C6)]+(Pic) {Ln = La, Ce, Pr, Nd, Sm, Gd} and [Ln(Pic)3(OH2)3] · 2(18C6) · 4H2O {Ln = Tb, Ho} complexes. The La-Gd complexes crystallized in an orthorhombic with space group Pbca, while the Ho complex crystallized in triclinic with space group . The lighter lanthanides complexes [La-Sm] had a 10-coordination number from the 18C6 ligand and the two picrates, forming a bicapped square-antiprismatic geometry. Meanwhile, the middle lanthanide complex [Gd] had a nine-coordination number from the 18C6 ligand and the two picrates, forming a tricapped trigonal prismatic geometry. The heavier lanthanide [Ho] is rather unique, since Ho(III) coordinated with nine oxygen atoms from three picrates and three water molecules in the opposite direction whereas three 18C6 molecules surrounded in the inner coordination sphere, forming a trigonal tricapped prismatic geometry. The 18C6 ligand is effective in controlling the molecular geometry and coordination bonding of Ln-O and can use a crystal engineering approach. No dissociation of Ln-O bonds in solution was observed in NMR studies conducted at different temperatures. The photoluminescence spectrum of the Pr complex has typical 4f-4f emission transitions, i.e. 3P0 → 3F2 (650 nm), 1D2 → 3F2 (830 nm) and 1D2 → 3F4 (950 nm).  相似文献   

18.
《Polyhedron》1999,18(8-9):1247-1251
One new diferrocene Schiff base was prepared by condensing 1′-formyl[(2,2-diferrocenyl)propane] with isonictinoyl hydrazine. 1′-formyl[(2,2-diferrocenyl)propane]isonicotinoyl hydrazone (HL) and its chelates with lanthanide ions, Ln(HL)2Cl3(H2O)n (Ln=La, Dy, Yb, Gd, Sm, Nd; n=1–5.) were prepared, isolated and characterized by elemental analysis, IR and 1H NMR spectra. In these chelates the ligand coordinates to lanthanide ions in the keto form, and some chloride ions and water molecules participate in coordination to the metal ion. The redox properties of the ligand and its complexes were investigated using cyclic voltammetric method. Both the ligand and its lanthanide complexes exhibit two distinct pairs of redox peaks displaying electrochemical characteristics of multi-component system.  相似文献   

19.
Twelve 5, 10, 15, 20‐tetra[(4‐alkoxy‐3‐ethyloxy)phenyl]porphyrin hydroxylanthanide complexes Ln[(C n OEOP)4P](OH) (n?=?12, 14, 16;Ln?=?Tb, Dy, Er, Yb) and three ligands have been synthesized and their composition, structure and spectral properties studied. Their liquid crystalline behaviour is also presented. Differential scanning calorimetry and polarizing optical microscopy reveal that all exhibit a discotic liquid crystalline phase. X‐ray diffraction shows that the mesophase is a hexagonal columnar, Colh. The lanthanide ion, which is coordinated to the four nitrogen atoms of the porphyrin and to the oxygen atom of the hydroxyl group, is out of the porphyrin molecular plane. All the complexes are stable below 200°C and undergo complete decomposition at 800°C. The fluorescence quantum yields of the lanthanide complexes are much lower than those of the corresponding ligands. The electrochemical studies show that the redox potentials do not change on varying the chain length.  相似文献   

20.

We proposed a new approach to the synthesis of heteroleptic crown-substituted terbium(III) bisphthalocyaninate, [(15C5)4Pc]Tb(Pc) (1) based on the reaction of unsubstituted lanthanum bisphthalocyaninate (La(Pc)2) with tetra-15-crown-5-phthalocyanine (H2[(15C5)4Pc]) and terbium(III) acetate in a mixture of octanol and chloronaphthalene in the presence of 1,8-diazabicyclo[ 5.4.0]undec-7-ene as an organic base. For the first time, we carried out a comparative spectrophotometric titration of compound 1 with MBPh4 solutions (M = K, Rb, Cs) and demonstrated the formation of isostructural cofacial supramolecular dimers. Spectral-structural correlations were developed for evaluation of the distances between phthalocyanine ligands in new supramolecular assemblies, which can be used for the development of polynuclear suprasingle-molecule magnetic materials.

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