Synthesis, characterization and fluorescence properties of novel pyridine dicarboxylic acid derivatives and corresponding Tb(III) complexes

Two novel ligands containing two pyridine-2,6-dicarboxylic acid conjugative units, 4-(2-(2,6-dicarbox-ypyridin-4-yl)vinyl)pyridine-2,6-dicarboxylic acid (L(1)) and 4-(4-(2-(2,6-dicarboxypyridin-4-yl)vinyl)styryl)pyridine-2,6-dicarboxylic acid (L(2)) and their complexes with Tb(III) have been synthesized and characterized by elemental analysis, IR spectra and NMR. The ligand synthetic route was optimized and the yield of ligands reached over 78% as a result of the Wittig-Horner reaction used. The fluorescent intensities of these complexes with corresponding complexes with single pyridine-2,6-dicarboxylic acid unit was compared. The result has shown that the ligands with two pyridine-2,6-dicarboxylic acid units are the excellent sensitizers to lanthanide fluorescence. Also, we investigated the fluorescence properties of these complexes in different solution and in different pH value. Due to their excellent green-emmiter, they would be a potential candidate material for applications in organic light-emitting devices and medical diagnosis.     

Simultaneous spectrophotometric determination of atrazine and cyanazine by chemometric methods

Three novel ligands containing pyridine-2,6-dicarboxylic acid unit, trans-4 -(4'-methoxystyryl) pyridine-2,6-dicarboxylic acid, trans-4-(4'-(dimethylamino)styryl)pyridine-2,6-dicarboxylic acid, and trans-4-(4'-(diphenylamino)styryl)pyridine-2,6-dicarboxylic acid were synthesized and their complexes with Eu(III), Tb(III) ions were successfully prepared. The ligands and the corresponding metal complexes were characterized by means of MS, elemental analysis, IR, (1)H NMR and TG-DTA. The luminescence spectra of Eu(III) and Tb(III) complexes in solid state were studied. The strong luminescence emitting peaks at 615 nm for Eu(III) and 545 nm for Tb(III) can be observed. The applications in cell imaging of the europium and terbium complexes were investigated.     

A new [2 + 1] mixed ligand concept based on [99(m)Tc(OH2)3(CO)3]+: a basic study

Mixed ligand fac-tricarbonyl complexes of the general formula [M(L1)(L2)(CO)3](M = Re, 99(m)Tc, L1= imidazole, benzyl isocyanide, L2 = 1H-imidazole-4-carboxylic acid, pyridine-2,4-dicarboxylic acid, pyridine-2,5-dicarboxylic acid) have been prepared starting from the precursors [M(OH2)3(CO)3]+. The complexes can be obtained in good yield and purity in a two-step procedure by first attaching the bidentate ligand followed by addition of the monodentate. 99mTc compounds can also be prepared at the tracer level in one-pot procedures with L1 and L2 being concomitantly present. This [2 + 1] approach allows the labeling of bioactive molecules containing a monodentate or a bidentate donor site. Examples given in here are N-(tert-butoxycarbonyl)glycyl-N-(3-(imidazol-1-yl)propyl)phenylalaninamide, 5-((3-(imidazol-1-yl)propyl)aminomethyl)-2'-deoxyuridine and 4-(5-isonitrilpentyl)-1-(2-methoxyphenyl)-piperazine as L1 and N-((6-carboxypyridine-3-yl)methyl)glycylphenylalanine as L2. The corresponding second ligand can be used to influence the physico-chemical properties of the conjugate. The crystal structures of [99Tc(OH2)(imc)(CO)3], [Re(OH2)(2,4-dipic)(CO)3], [Re(bic)(2,4-dipic)(CO)3] and [Re(im)(2,5-dipic)(CO)3] are reported.     

Adamantane and its derivatives. 1. Hydrazones and pyrazolones of adamantane

The dihydrazones, bis(diphenylhydrazones), and bis (2,4-dinitrophenylhydrazones) of adamantanone-2-carboxylic acid, dimethyl adamantane-2,6-dione-1,5-dicarboxylate, and tetramethyl adamantane-2,6-dione-1,3,5,7-tetracarboxylate and the pyrazolones of the corresponding acids were synthesized. It is shown that the methyl esters of adamantane-2,6-dione-1,5-dicarboxylic and -1,3,5,7-tetracarboxylic acids and their hydrazones cannot be converted to adamantane-1,5-dicarboxylic and -1,3,5,7-tetracarboxylic acids under the conditions of the Huang-Minlon and Locke reactions.Translated from Khimiya Geterotsiklicheskikh Soedinenii, No. 4, pp. 528–531, April, 1982.     

Thermal properties of some complexes of quinolinic acid with divalent metal ions

Studies of the complexes of pyridinecarboxylic acids with divalent metal ions as a function of the position of the carboxyl groups were extended. The thermal properties of the complexes of quinoline acid (pyridine-2,3-dicarboxylic acid) with several divalent metal ions were determined by thermogravimetry (TG) and differential thermal analysis (DTA). A correlation between these compounds and others obtained by reaction between the studied metal ions with similar acids (lutidinic acid (pyridine-2,4-dicarboxylic acid) and isocinchomeronic acid (pyridine-2,5-di-carboxylic acid) is discussed in terms of the position of the carboxyl group far from the aza group. The thermal stability of the metal complexes is in the order Mn(II) > Fe(II) > Zn(II) ? Co(II) > Ni(II) > Cu(II).     

吡啶-2,6-二甲酰腙类化合物及其Tb(Ⅲ)和Eu(Ⅲ)配合物的合成与荧光性能

吡啶-2,6-二甲酸经酯化,肼解得吡啶-2,6-二甲酰肼(2),(2)与芳香醛缩合得到了3个新的酰腙配体:吡啶-2,6-二甲酰肼苯甲醛腙(3a)、吡啶-2,6-二甲酰肼水杨醛腙(3b)和吡啶-2,6-二甲酰肼呋喃甲醛腙(3c),其结构经元素分析、IR、1HNMR和MS进行了确认。制备了吡啶-2,6-二甲酰肼与这三种新型配体的Tb(III)和Eu(III)配合物,并对配合物的溶液态的荧光性质进行了研究。结果表明,吡啶-2,6-二甲酰肼苯甲醛腙(3a)和吡啶-2,6-二甲酰水杨醛腙(3b)作为荧光敏化剂,对Eu3+和Tb3+的荧光敏化性能比吡啶-2,6-二甲酰肼以及大多数吡啶-2,6-二甲酸衍生物要好,是较理想的稀土荧光敏化剂,它们的稀土配合物在分子偶极矩较小的溶剂中荧光强度较强。     

A Chain Structure Based on Homodinuclear Scandium Units： [Sc（μ-OH）（2,5-pydc）（H2O）]n

The reaction of pyridine-2,5-dicarboxylic acid with Sc2O3 under hydrothermal con- dition yields a new complex [Sc（μ-OH）（2,5-pydc）（H2O）]n 1 which has a chain structure based on homodinuclear scandium units. Crystal data for 1： space group P^-1, a = 6.7192（13）, b = 7.6131（13）, c = 8.9313（14） A, α = 95.976（6）, β = 101.663（6）, γ = 108.151（5）^o, V= 418.26（13） A^3, Z = 2, Dc = 1.946 g/cm^3, g = 0.889 mm^-1, F（000） = 248, C7H6NO6Sc, Mr = 245.09, the final R = 0.0429 and wR = 0.1086.     

Efficient Synthesis of 3-(4-Carboxyphenyl)pyridine-2,6-dicarboxylic Acid

Russian Journal of Organic Chemistry - An efficient synthetic approach to 3-(4-carboxyphenyl)pyridine-2,6-dicarboxylic acid has been developed on the basis of “1,2,4-triazine”...     

Synthesis of unsaturated esters of pyridine-and quinolinecarboxylic acids

The vinyl esters of pyridine-2-and -4-carboxylic acids, the propargyl esters of pyridine-2-, -3-, and-4-carboxylic acids, the vinyl, allyl, and propargyl esters of quinoline-2-, -4-, and -8-carboxylic acids, and the allyl ester of 2-methylisonicotinic acid have been synthesized.     

Synthesis of Macroheterocycles Containing Pyridine-2,6-dicarboxylic and Adipic Acid Ester and Hydrazide Fragments Starting from Tetrahydropyran

Russian Journal of Organic Chemistry - Efficient methods have been developed for the synthesis of three potentially useful macroheterocycles containing pyridine-2,6-dicarboxylic and adipic acid...     

Synthesis of Eu(III) and Tb(III) complexes with novel pyridine dicarboxylic acid derivatives and their fluorescence properties

Starting from pyridine-2,6-dicarboxylic acid (DPA), a series of novel pyridine-2,6-dicarboxylic acid derivatives were synthesized. In these compounds, 4-(hydroxymethyl)pyridine-2,6-dicarboxylate (4-HMDPA) and 4-[(bis-carboxymethyl-amino)-methyl]-pyridine-2,6-dicarboxylic acid (4-BMDPA) were used as multifunctional ligands to coordinate with Tb(III) and Eu(III) and the complexes were prepared. The fluorescence properties of the solid complexes and their solutions were investigated in detail. The results indicated that the weak election-withdrawing group 4-hydroxymethyl in 4-position of pyridine in 4-HMDPA could weaken the fluorescence intensity of the lanthanide complexes. The contradistinctive experimental results showed that the fluorescence intensities of these complexes are related to pH values of the aqueous solutions and the dipole moments of solvent molecules: in the neutral aqueous solutions, the fluorescence intensities of these complexes were strongest, while the dipole moments were lower when the fluorescence intensities were stronger. 4-BMDPA is the better sensitizer and may be used as time-resolved fluoroimmunoassay. __________ Translated from Chemical Journal of Chinese Universities, 2006, 27(3) (in Chinese)     

Esterification of pyridinecarboxylic acids in the presence of cation-exchange resins

Pyridinecarboxylic acids undergo esterification on refluxing with alcohols in the presence of cation-exchange resins. In the case of pyridine-2,6-dicarboxylic acid, in which the basicity of the nitrogen atom is reduced, esterification products are obtained in high yields. In the case of pyridinecarboxylic acids, in which the pyridine nitrogen atom displays considerable basicity, the cations of the acids are tied up by the cation-exchange resin, and the yields of preparatively isolable esters do not exceed 60%.Translated from Khimiya Geterotsiklicheskikh Soedinenii, No. 2, pp. 233–237, February, 1976.     

Synthesis of 4-Halofuro[3,4-c]pyridin-3(1H)-ones from 2-Halopyridine-3,4-dicarbonitriles

Russian Journal of Organic Chemistry - Heating of 2-halopyridine-3,4-dicarboxylic acids in propionic anhydride led to the formation of 4-halofuro[3,4-c]pyridine-1,3-diones as a result of...     

Regio- and stereoselectivity of cycloaddition of C-amidonitrones to esters of methylenecyclopropanedicarboxylic acids

C-Amidonitrones add regio- and stereoselectively to esters of 3-methylenecyclopropane-1,2-dicarboxylic, 2-(diphenylmethylene)cyclopropane-1,1-dicarboxylic, and 2-(1-phenylethylidene)cyclopropane-1,1-dicarboxylic acids to form a single diastereomer of 4-spirocyclopropaneisoxazolidines.     

Synthesis of polyesters containing acetylenic bonds in the chain

Summary By joint oxidative dehydropolycondensation of p-diethynylbenzene and dipropargyl esters, polymers have been obtained that contain triple bonds alternating with ester groups.     

Electrochemical reduction of 1, 4-dihydropyridine-3, 5-dicarboxylic acid derivatives in an aprotic medium

The polarographic reduction of 1, 4-dihydropyridine-3, 5-dicarboxylic acid derivatives in dimethylformamide was studied. It is shown that the first diffusion waves of these compounds are irreversible one-electron waves and correspond to electrical reduction of the C=C bond of the conjugated system of the 1, 4-dihydropyridine ring to give a tetrahydro derivative. In the case of pyridine-3, 5-dicarboxylic acid esters partial dimerization of the resulting freeradical products occurs along with electron transfer. It is shown that the introduction of alkoxycarbonyl substituents in 2, 6-methyl and 3, 5-methoxycarbonyl groups and in the 4 position and of a carboxyl group in the 4 position facilitates the electrical reduction of the 1, 4-dihydropyridine ring. The introduction of a methyl group in the 4 position hinders reduction of the ring.Translated from Khimiya Geterotsiklicheskikh Soedinenii, No. 5, pp. 641–646, May, 1978.     

Preparation of differentiated diamides of 4,5,6,7-tetrahydropyrazolo[1,5-<Emphasis Type="Italic">a</Emphasis>]pyridine-2,6- and −3,6-dicarboxylic acids suitable for parallel synthesis

1,3-Dipolar cycloaddition of a bicyclic sydnone to a propargylic acid amide affords 4,5,6,7-tetra-hydropyrazolo[1,5-a]pyridine-2,6- and −3,6-dicarboxylic acid monoamides which are further converted to corresponding differentiated diamides.     

异核配合物K2[Co(Dipc)2]·7H2O的合成、性质、结构和热分解动力学研究

A heteronuclear compound, K₂[Co(Dipc)₂]·7H₂O (Dipc=pyridine-2,6-dicarboxylic acid) has been synthe- sized and characterized by IR, elemental analysis, and X-ray diffraction. Crystal data: orthorhombic system with space group Pnna and unite cell parameters: a=2.0645(3)nm, b=1.3484(2)nm, c=0.8204(1)nm; V=2.2838(6)nm³, Z=4, D_cald=1.726 g·cm^-3, μ=1.193 mm^-1, F(000)=1212, Gof=1.045, Δρ=339～-348 e·nm^-3, the final R is 0.0295. In the molecule of the complex, Co(Ⅱ) ion is six-coordinate to form a dis-torted octahedron. The N atom and the carboxyl group of pyridine-2,6-dicarboxylic acid are coordinated with the central ions. One of the carboxyl groups of the pyridine-2,6-dicarboxylic acid connect K(Ⅰ) and Co(Ⅱ). The com- pound possesses approximate C₂ symmetry. The compounds form a three-dimensional network of infinite length connection with crystal waters, potassium ions and hydrogen bonds. The result of kinetics of thermal decomposition indicated that the compound decomposition takes place in two steps. CCDC: 207078.     

Lanthanum(III) complex as ferromagnetic supraprecursor for preparation of La2O3 nanoparticles by thermal decomposition method

Research on Chemical Intermediates - A metal–organic framework lanthanum(III) complex with formula ([La(pydc)2(H2O)3]·4H2O)n (1), where pydc?=?pyridine-2,6-dicarboxylic acid,...     

A New Pyridine-3,4-dicarboxylic Acid Bridged Zinc(Ⅱ) Coordination Complex: Crystal Structure,Quantum Chemistry and Luminescence Property

A new 2D metal coordination polymer, [Zn(pydc)(L)(H_2O)]_n·5nH_2O(1, H_2pydc = pyridine-3,4-dicarboxylic acid, L = 3-(2-pyridyl)pyrazole), was synthesized under hydrothermal conditions and characterized by single-crystal X-ray diffraction, powder XRD, FT-IR, thermogravimetric, fluorescence spectrum and elemental analysis techniques. Complex 1 belongs to the monoclinic system, P2_1/c space group, with a =10.707(5), b = 14.221(5), c = 13.278(5) ?, β = 102.071(5)°, V = 1977.1(14) ?~3 and Z = 2. It features a 2D network constructed by pydc~(2-) and L ligand. In addition, the quantum-chemical calculations were accomplished on ‘molecular fragments' extracted from the crystal structure of 1 using the PBE0/LANL2DZ method built in Gaussian 16 Program. The calculation values denoted the distinct covalent interaction between the coordinated atoms and Zn(Ⅱ) ion.