Quinaldinic Acid Research Articles

The [Zn(NH3)4]2+ reactions with quinaldinate or pyrazinoate: A ready synthetic route to zinc(II) coordination polymers?

The reaction of [Zn(NH3)4]2+ in aqueous ammonia solution with quinaldinic acid (quinoline-2-carboxylic acid) gave a mononuclear heteroleptic ammine/quinaldinate complex with the [Zn(quin)2(NH3)] composition. The introduced secondary ligand adopted the usual N,O-bidentate chelating coordination. In the analogous reaction with pyrazinoic acid (pyrazine-2-carboxylic acid), complete substitution of ammonia with pyrazionate and water was observed. A mixture of two compounds formed: a mononuclear and already known [Zn(pyraz)2(H2O)2] and a novel one-dimensional (1D) coordination polymer [Zn(pyraz)2(H2O)]n. X-ray structure analysis revealed the pyrazinoate ligands in [Zn(pyraz)2(H2O)]n in two binding modes, in a bidentate chelating coordination and in a tridentate bridging coordination. The bridging pyrazinoate has engaged in binding three out of four donors: a carboxylate oxygen and both nitrogen atoms. A detailed presentation of the structure of [Zn(pyraz)2(H2O)]n and its comparison with the structures of related compounds are given below.

Chemoenzymatic Enantioselective Synthesis of the Hancock Alkaloids (S)- and (R)-Galipeine, (S)-Cuspareine, (S)-Galipinine, and (S)-Angustureine

AbstractThe enantioselective synthesis of the Hancock 1,2,3,4-tetrahydroquinoline alkaloids (S)-galipeine, (S)-cuspareine, (S)-galipinine, and (S)-angustureine and the nonnatural enantiomer (R)-galipeine is described herein. The target compounds were obtained in five steps from a racemic quinaldinic acid derived α-amino ester in overall yields of 21.2% to 37.5%. The synthetic route comprised two key steps: an enzymatic kinetic resolution to control the C-2 stereocenter, affording (R)- and (S)-α-amino esters as key chiral intermediates with 94% and 72% ee, respectively, and Wittig olefination of (R)- and (S)-α-amino aldehyde synthons with the corresponding phosphonium salts using a phase-transfer system (t-BuOH/CH2Cl2), thereby allowing the introduction of alkyl substituents at C-2. Finally, the enantioselective synthesis was concluded with the catalytic hydrogenation of olefinic bonds on the Wittig adducts to furnish the target Hancock alkaloids, including (R)-galipeine, whose synthesis is described here for the first time.

Hydrogen Bonding and Polymorphism of Amino Alcohol Salts with Quinaldinate: Structural Study.

Three amino alcohols, 3-amino-1-propanol (abbreviated as 3a1pOH), 2-amino-1-butanol (2a1bOH), and 2-amino-2-methyl-1-propanol (2a2m1pOH), were reacted with quinoline-2-carboxylic acid, known as quinaldinic acid. This combination yielded three salts, (3a1pOHH)quin (1, 3a1pOHH+ = protonated 3-amino-1-propanol, quin− = anion of quinaldinic acid), (2a1bOHH)quin (2, 2a1bOHH+ = protonated 2-amino-1-butanol), and (2a2m1pOHH)quin (3, 2a2m1pOHH+ = protonated 2-amino-2-methyl-1-propanol). The 2-amino-1-butanol and 2-amino-2-methyl-1-propanol systems produced two polymorphs each, labeled 2a/2b and 3a/3b, respectively. The compounds were characterized by X-ray structure analysis on single-crystal. The crystal structures of all consisted of protonated amino alcohols with NH3+ moiety and quinaldinate anions with carboxylate moiety. The used amino alcohols contained one OH and one NH2 functional group, both prone to participate in hydrogen bonding. Therefore, similar connectivity patterns were expected. This proved to be true to some extent as all structures contained the NH3+∙∙∙−OOC heterosynthon. Nevertheless, different hydrogen bonding and π∙∙∙π stacking interactions were observed, leading to distinct connectivity motifs. The largest difference in hydrogen bonding occurred between polymorphs 3a and 3b, as they had only one heterosynton in common.

Beyond the Simple Copper(II) Coordination Chemistry with Quinaldinate and Secondary Amines.

Copper(II) acetate has reacted in methanol with quinaldinic acid (quinoline-2-carboxylic acid) to form [Cu(quin)2(CH3OH)]∙CH3OH (1) (quin− = an anionic form of the acid) with quinaldinates bound in a bidentate chelating manner. In the air, complex 1 gives off methanol and binds water. The conversion was monitored by IR spectroscopy. The aqua complex has shown a facile substitution chemistry with alicyclic secondary amines, pyrrolidine (pyro), and morpholine (morph). trans-[Cu(quin)2(pyro)2] (2) and trans-[Cu(quin)2(morph)2] (4) were obtained in good yields. The morpholine system has produced a by-product, trans-[Cu(en)2(H2O)2](morphCOO)2 (5) (morphCOO− = morphylcarbamate), a result of the copper(II) quinaldinate reaction with ethylenediamine (en), an inherent impurity in morpholine, and the amine reaction with carbon dioxide. (pyroH)[Cu(quin)2Cl] (3) forms on the recrystallization of [Cu(quin)2(pyro)2] from dichloromethane, confirming a reaction between amine and the solvent. Similarly, a homologous amine, piperidine (pipe), and dichloromethane produced (pipeH)[Cu(quin)2Cl] (11). The piperidine system has afforded both mono- and bis-amine complexes, [Cu(quin)2(pipe)] (6) and trans-[Cu(quin)2(pipe)2] (7). The latter also exists in solvated forms, [Cu(quin)2(pipe)2]∙CH3CN (8) and [Cu(quin)2(pipe)2]∙CH3CH2CN (9). Interestingly, only the piperidine system has experienced a reduction of copper(II). The involvement of amine in the reduction was undoubtedly confirmed by identification of a polycyclic piperidine compound 10, 6,13-di(piperidin-1-yl)dodecahydro-2H,6H-7,14-methanodipyrido[1,2-a:1′,2′-e][1,5]diazocine.

Special features of the interaction of pyridine and quinoline derivatives, and related compounds with triphenylphosphine

Using pyridine, quinoline, and related compounds as examples, it has been shown that their interaction with triphenylphosphine occurs via different pathways. Reaction of triphenylphosphine with N-vinylisonicotinic acid chloride leads to the mixture of 1,2-bis(triphenylphosphoniumchlorido)ethane and 4-carboxy-2-(triphenylphosphoniumchloridoethyl)pyridine. In the case of α-(N-2-carboxyquinolinylbromido)-β-bromopropionic acid, the reaction with triphenylphosphine proceeds via phosphine attack on the oxygen atom with elimination of quinaldinic acid, and subsequent nucleophilic substitution with the formation of 3-(triphenylphosphoniumbromido) propionic acid bromide.

Sensitized Luminescence of Trivalent Lanthanide Complexes Eu3+/Quinaldinic Acid and Eu3+/1,4-Dihydro-Oxo-Chinoline-3-Carboxilic Acid

Studies of the luminescence of Eu(3+)/quinaldinic acid sodium [Eu(QA)(3)] and Eu(3+)/1,4-dihydro-4-oxo-quinoline-carboxylic acid sodium [Eu/(DOQCA)(3)], both in solid form and in aqueous solution, are presented in room temperature. The energy transfer to the emitting levels of the lanthanide ions are discussed on the basis of the emission spectra and lifetime data of (5)D(0) and (5)D(1) levels of Eu(3+). In the aquated Eu/(QA)(3) complex, the most intense spectral band belongs to the (5)D(0) --> (7)F(1) transition (592 nm) and not to (5)D(0) --> (7)F(2) (616 nm), which otherwise occurs usually. In the cases of the Eu/(DOQCA)(3) complex the hypersensitive transition (5)D(0) --> (7)F(2) is the most intense as so far was reported for various Eu(3+) chelates.

Preparation and testing of standard solutions of cadmium, copper and lead

Solutions of Cd, Cu and Pb at concentrations of about 1000 mg/l were prepared by dissolving the pure metals in HNO3. Their concentration was verified by complexometric titration and by gravimetric analysis (Cu with salicylaldoxime, Cd with quinaldinic acid and Pb with 8-hydroxyquinoline). The results of the two methods were very similar and the uncertainty values were equal. However, the gravimetric determination can be regarded as more reliable, because titrimetric analysis is more prone to error due to inaccurate end-point reading. The expanded uncertainty of the concentrations of Cd and Cu attained 1 mg/l, which is half the value typically obtained for similar solutions from commercial manufacturers. To achieve such precise results, the bias had to be reduced by the highest possible extent, particularly by calibrating both the balance and the volumetric glassware. In addition to the uncertainty of the basic operations (volumetric and gravimetric), the uncertainty of the atomic and molecular weights constituted an appreciable component in the combined standard uncertainty; this manifested itself in the determination of Pb, where the expanded uncertainty was 2 mg/l.

Intramolecular hydrogen bonding in 8-quinolinol N-oxides, quinaldinic acid N-oxides and quinoline-2-carboxyamide N-oxide. Deuterium isotope effects on 13C chemical shifts

Secondary isotope effects on 13C chemical shifts have been measured in a series quinolinols, quinaldinic aci N-oxides and quinoline-2-carboxyamide N-oxide. For 8-quinolinol N-oxides a good correlation was found between δOH and nΔC(OD) isotope effects. The OH and 13C chemical shifts and n ΔC(OD) show very small temperature dependences. The primary isotope effects are small, positive and temperature insensitive. Furthermore, they increase with increasing n ΔC(OD). All features point towards a localised hydrogen bond in an asymmetric double well potential. The quinaldinic acid N-oxides show long-range isotope effects on 13C chemical shifts of both signs with 2 ΔCO(OD) rather small. The primary isotope effects of the quinaldinic acid N-oxide is of order of 0.5 ppm, whereas for its 4-ethoxy-derivative is smaller, ∼0.3 ppm. The OH chemical shifts resonate at the low field ∼18–20 ppm and the OH resonance is fairly broad at room temperature, especially for the 4-ethoxy-derivative. The temperature effects on the chemical shifts, primary and secondary isotope effects are small. For quinaldinic acid N-oxides the asymmetric broad quasi-single potential is suggested. For quinoline-2-carboxyamide N-oxide the isotope effects are small, indicating rather weak hydrogen bond

Alkali Metal Complexes: Mixed-ligand Complexes of Alkali Metal Salts of Picolinic Acid, Quinaldinic Acid and their N-Oxides with Ethylenediamine and Propylenediamine

Alkali Metal Complexes: Mixed-ligand Complexes of Alkali Metal Salts of Picolinic Acid, Quinaldinic Acid and their N-Oxides with Ethylenediamine and Propylenediamine

Alkali Metal Complexes: Mixed-ligand Complexes of Alkali Metal Salts of Picolinic Acid, Quinaldinic Acid and their N-Oxides with Ethylenediamine and Propylenediamine

Alkali Metal Complexes: Mixed-ligand Complexes of Alkali Metal Salts of Picolinic Acid, Quinaldinic Acid and their N-Oxides with Ethylenediamine and Propylenediamine

Preconcentration and Separation of Gold(III) and Silver(I) from each other and from Base Metals using a Chelating Ion-exchanger containing Quinaldinic Acid Amide Grouping

Preconcentration and Separation of Gold(III) and Silver(I) from each other and from Base Metals using a Chelating Ion-exchanger containing Quinaldinic Acid Amide Grouping

Synthesis of Quinaldinic Acid Amide Derivative of Styrene-Divinylbenzene Copolymer and its Application in Preconcentration of Mercury (II)

Abstract A new chelating resin has been synthesized by introducing a quinaldinic acid amide group into styrenedivinyl benzene (8%) copolymer beads. The resin is stable in fairly strong acids or alkali and has been characterized by elemental analysis for nitrogen and from i.r. spectra. The water regain value is 0.37g/g. The sorption patterns of Na(I), K(I), Ca(II), Mg(II), Pb(II), Cu(II), Ni(II), Zn(II), Cd(II), Hg(II) and Fe(III) on the chelating resin have been studied as a function of pH. The resin selectively sorbs Hg(II) ever a wide pH-range of 2.5–7.6 with high efficiency. The maximum exchange capacity for Hg(II) is 1.98 mmols g−1 at pH 5.5. Over 99% of Hg(II) sorbed has been recovered by using 10% thiourea in 1M HClO4 both by batch and column operations. The has been utilized in the preconcentration and recovery of Hg(II) from industrial and laboratory waste water.

Alkali metal complexes: Mixed ligand complexes of alkali metal salts of some organic acids with picolinic acid N-oxide and quinaldinic acid N-oxide

Abstract A number of mixed ligand complexes of alkali metal salts of o-nitrophenol, 1- nitroso-2-naphthol and 8-hydroxyquinoline has been synthesized and characterized. IR studies indicate the presence of hydrogen bonding. Ease of complexation as well as the yield has been found to increase with the increase in radius of alkali metal cations. Low values of their molar conductivities suggest that they are non-electrolytes.

Alkali Metal Complexes. Mixed Ligand Complexes of Alkali Metal Salts of some Organic Acids with Picolinic Acid and Quinaldinic Acid

Alkali Metal Complexes. Mixed Ligand Complexes of Alkali Metal Salts of some Organic Acids with Picolinic Acid and Quinaldinic Acid

Alkali metal complexes: Complexes of alkali metals with quinaldinic acid

Complexes having the general formula ML.HL, where M = Na, K, Rb or Cs and HL = quinaldinic acid, have been obtained. The isolation of adducts in the solid state appeared to be favoured by increase in atomic radius, and hence decrease in ionisation potential of the metal. Attempts to synthesise similar adducts of picolinic acid N-oxide and quinaldinic acid N-oxide did not succeed. Complexes have been characterised by elemental analyses, thermal, IR spectral and solution studies. Our findings suggest that pK value of the ligands cannot be regarded a dominant factor in the synthesis and isolation of alkali metal complexes.

Studies on complex compounds of thorium(IV) with pyridine and quinoline carboxylic acid. Part I

Thorium acetylacetonate [Th(acac)4] reacts with pyridine carboxylic acids in acetone giving eight coordinate thorum(IV) complexes of the compositions [Th(pic)4] and [Th(picO)4] (picH = picolinic acid, picOH = picolinic acidN-oxide). The complex [Th(dip)2] · 3H2O (dipH2 = pyridine-2,6-dicarboxylic acid) is also reported. Thorium(IV) complexes of the types [Th(quin)2] · 2H2O and [Th(quind)2(acac)2] (quinH2 = quinolinic acid or pyridine-2,3-dicarboxylic acid, quindH = quinaldinic acid) were prepared by the interaction of [Th(acac)4] with the respective acids in acetone. The lower solubility and i.r. spectral studies of the complex [Th(quin)2] · 2 H2O suggest that it is polymeric.

Studies on tertiary amine oxides. LXVII . Reactions of aromatic N‐oxides with 3‐arylrhodanines in the presence of acetic anhydride

AbstractQuinoline 1‐oxides 1 readily react with 3‐arylrhodanines 2 in the presence of acetic anhydride to afford 3‐aryl‐5‐(2‐quinolyl)rhodanines 3 in high yields. These products resist hydrolysis under both alkaline and acidic conditions, but is oxidized to quinaldinic acid 1‐oxide 4 with 30% hydrogen peroxide in hot acetic acid. Besides isoquinoline 2‐oxide 5, pyridine 1‐oxide 7a also reacts in the same way to give 3‐aryl‐5‐(2‐pyridyl)rhodanines 8, although the reactivity of γ‐picoline 1‐oxide 7b is considerably lower. Contrary to 3, 3‐phenyl‐5‐(2‐pyridyl)rhodanine 8a is successfully hydrolyzed with boiling 48% hydrobromic acid to 2‐pyridinemethanethiol 10 in 57% yield.

Studies on mixed ligand complexes, part 5. Heterochelate complexes of cobalt(III) derived from the quadridentate NNNN donor ligand triethylenetetramine and bidentate OO, ON and NN donor ligands

A series of new cobalt(III) complexes of general formula [Co(AA)(trien)]Xn (where AA = tropolone, acetoacetanilide, ethylacetoacetate, biguanide, 2-guanidinobenzimidazole, propylenediamine, picolylamine, 2,2′-dipyridyl, 3-aminopyridine, picolinic acid and quinaldinic acid, trien = triethylenetetramine, X=Cl−, Br−, I− and n=2–3) have been synthesized and characterized by elemental analysis, electronic and i.r. spectra, equivalent weight, conductance and magnetic measurements. The electronic spectra of the complexes exhibit one or two ligand field bands atca. 20000 and 29000 cm−1 due to the1A1g→1T1g and1A1g→1T2g transitions respectively. Conductance measurements indicate the triunivalent nature of [Co(tropolone)(trien)]I3, [Co(picolylamine)(trien)]I3, [Co(3-aminopyridine)(trien)]I3, [Co(2,2′-dipyridyl)(trien)]Cl3, [Co(biguanide)(trien)]I3, [Co(propylenediamine)(trien)]I3 and biunivalent nature of [Co(picolinate)(trien)]Cl2, [Co(quinaldinate)(trien)]Cl2, [Co(acetoacetanilido)(trien)]Cl2, and [Co(ethylacetoacetato)(trien)]I2. Equivalent weight determination by the ion-exchange resin (H+ form) method gives the values of molecular weights which are consistent with the theory. The complexes are diamagnetic.

Kinetic study on the conversion of pyridine‐ and quinolinecarboxylic acids to the corresponding trichloromethyl compounds

AbstractThe reaction rates of the conversion of various substituted picolinic and quinaldinic acids to the corresponding trichloromethylpyridines and quinolines by treatment with phosphorus pentachloride in refluxing thionyl chloride have been measured, and the apparent second‐order kinetic constants determined. The logarithmic rate constants (log k) were found to be linear with the basicities (pKa) of the unsaturated ring nitrogens in the substrates. The reaction constant, p, of the conversion was estimated.

STUDIES ON COMPLEX COMPOUNDS OF URANIUM(IV) WITH PYRIDINE AND QUINOLINE CARBOXYLIC ACID. PART II

The reactions between bis(pyridine-2,6-dicarboxylato)-uranium(IV), U(dip)/sub 2/ and N-heterocyclic bases (L) in methanol (L = pyridine, 2-methylpyridine, 3-methylpyridine and 4-methylpyridine) produce eight coordinate uranium(IV) complexes, U(dip)/sub 2/(H/sub 2/O)L which have been characterized by elemental analysis, ir studies, thermal analysis and magnetic susceptibility measurement. The anionic complex (Ph/sub 4/As)/sub 2/(U(dip)/sub 3/), 3H/sub 2/O has been isolated by reacting U(dip)/sub 2/ with pyridine-2,6-dicarboxylic acid in the presence of tetraphenyl arsonium chloride. Uranium(IV) complexes of the type U(quind)/sub 2/(acetate)/sub 2/, U(quin)(acetate)/sub 2/ (quindH = quinaldinic acid, quinH/sub 2/ = quinolinic acid, acetate = CH/sub 3/COO/sup -/) have also been prepared by the interaction of the methanolic solution of uranium tetraacetate and the respective acids.