Copper(II) Dihydroxybenzoates; Synthesis and Properties

1993 ◽  
Vol 58 (6) ◽  
pp. 1363-1370 ◽  
Author(s):  
Jozef Sokolík ◽  
Brigita Lučanská ◽  
Gustáv Plesch ◽  
Ingrid Tumová ◽  
Aladár Valent ◽  
...  
Keyword(s):  
Carboxylic Acids ◽  
Electronic Spectra ◽  
Room Temperature ◽  
Magnetic Moments ◽  
Tetragonal Distortion ◽  
High Toxicity ◽  
Antipyretic Activity ◽  
Pharmacological Screening ◽  
Cooperative Ordering

Compounds of composition Cu(2,5-DHB)2 . 4 H2O (DHB, dihydroxybenoate anion) and Cu(2,Y-DHB)2 . 8 H2O (Y = 4 or 6) were prepared as potential antiinflamatory gents with a view of pharmacological screening. The room-temperature magnetic moments allow to classify all compounds into the group of magnetically diluted copper(II) complexes. According the EPR and electronic spectra, the degree of tetragonal distortion increases passing from Cu(2,6-DHB)2 . 8 H2O (III) through Cu(2,4-DHB)2 . 8 H2O (I) to Cu(2,5-DHB)2 . 4 H2O (II. The complexes differ also in the cooperative ordering in their structures. All tested compounds exhibit higher antiinflamatory activities (on dextran edema) than free carboxylic acids. However, their effects were accompanied with relatively high toxicity. Remarkable results were also achieved on evaluating the antipyretic activity.

scholarly journals 3D Metal–Organic Frameworks Based on Co(II) and Bithiophendicarboxylate: Synthesis, Crystal Structures, Gas Adsorption, and Magnetic Properties

Molecules ◽  
2021 ◽  
Vol 26 (5) ◽  
pp. 1269
Author(s):  
Vadim A. Dubskikh ◽  
Anna A. Lysova ◽  
Denis G. Samsonenko ◽  
Alexander N. Lavrov ◽  
Konstantin A. Kovalenko ◽  
...  
Keyword(s):  
Room Temperature ◽  
Gas Adsorption ◽  
Magnetic Moments ◽  
Bet Surface Area ◽  
Separation Performance ◽  
Bridging Ligands ◽  
Magnetization Data ◽  
Metal Organic ◽  
Ch4 Adsorption ◽  
Gas Separation Performance

Three new 3D metal-organic porous frameworks based on Co(II) and 2,2′-bithiophen-5,5′-dicarboxylate (btdc2−) [Co3(btdc)3(bpy)2]·4DMF, 1; [Co3(btdc)3(pz)(dmf)2]·4DMF·1.5H2O, 2; [Co3(btdc)3(dmf)4]∙2DMF∙2H2O, 3 (bpy = 2,2′-bipyridyl, pz = pyrazine, dmf = N,N-dimethylformamide) were synthesized and structurally characterized. All compounds share the same trinuclear carboxylate building units {Co3(RCOO)6}, connected either by btdc2– ligands (1, 3) or by both btdc2– and pz bridging ligands (2). The permanent porosity of 1 was confirmed by N2, O2, CO, CO2, CH4 adsorption measurements at various temperatures (77 K, 273 K, 298 K), resulted in BET surface area 667 m2⋅g−1 and promising gas separation performance with selectivity factors up to 35.7 for CO2/N2, 45.4 for CO2/O2, 20.8 for CO2/CO, and 4.8 for CO2/CH4. The molar magnetic susceptibilities χp(T) were measured for 1 and 2 in the temperature range 1.77–330 K at magnetic fields up to 10 kOe. The room-temperature values of the effective magnetic moments for compounds 1 and 2 are μeff (300 K) ≈ 4.93 μB. The obtained results confirm the mainly paramagnetic nature of both compounds with some antiferromagnetic interactions at low-temperatures T < 20 K in 2 between the Co(II) cations separated by short pz linkers. Similar conclusions were also derived from the field-depending magnetization data of 1 and 2.

scholarly journals Mechanically induced solvent-free esterification method at room temperature

RSC Advances ◽  
2021 ◽  
Vol 11 (9) ◽  
pp. 5080-5085
Author(s):  
Lei Zheng ◽  
Chen Sun ◽  
Wenhao Xu ◽  
Alexandr V. Dushkin ◽  
Nikolay Polyakov ◽  
...  
Keyword(s):  
Natural Products ◽  
Carboxylic Acids ◽  
Late Stage ◽  
Reaction Mechanisms ◽  
Room Temperature ◽  
Solvent Free ◽  
Mild Conditions

We have developed I2/KH2PO2 and KI/P(OEt)3 strategy syntheses of esters from carboxylic acids and alcohols through different reaction mechanisms. The advantages of present protocol: mild conditions and late-stage diversification of natural products.

Room-temperature Barbier single-atom polymerization induced emission as a versatile approach for the utilization of monofunctional carboxylic acid resources

2021 ◽  
Author(s):  
Quan-Xi Shi ◽  
Qian Li ◽  
Hang Xiao ◽  
Xiaoli Sun ◽  
Hongli Bao ◽  
...  
Keyword(s):  
Carboxylic Acid ◽  
Carboxylic Acids ◽  
Building Block ◽  
Room Temperature ◽  
Single Atom ◽  
The Earth

Carboxylic acids are widely available from both biomass and fossil sources on the earth. In comparison with multifunctional carboxylic acid containing chemicals those have been comprehensively used as building block...

scholarly journals Complexes of Pyridine-2-carbaldehyde S-Methylthiosemicarbazone with nickel(II) and copper(II)

1974 ◽  
Vol 27 (5) ◽  
pp. 1133 ◽  
Author(s):  
MA Malik ◽  
DJ Phillips
Keyword(s):  
Electronic Spectra ◽  
Magnetic Moments ◽  
Tridentate Ligands ◽  
Pale Yellow ◽  
Nickel Perchlorate

New complexes of pyridine-2-carbaldehyde S-methylthiosemicarbazone (pmts) with nickel(11) and copper(11) are reported, together with magnetic moments, infrared and electronic spectra. The pale yellow bis-ligand complexes with nickel perchlorate, tetrafluoroborate and nitrate have the ionic structures [Ni(pmts)2] X2, with six-coordinate nickel(11) and tridentate ligands. Thiocyanate co-ordination and bidentate pmts appear to be present in the six-coordinate orange-brown complex Ni(pmts)2(NCs)2. The complexes, Ni(pmts)X2 (X = Cl, Br), are halogen-bridged and six-coordinate. The complexes Cu(pmts)X2 (X = Cl, Br, NO3) do not appear to be five coordinate, and may be six coordinate.

Efficient synthesis of pyrido[2,3-d]pyrimidine-7-carboxylic acids catalyzed by a TiO2/SiO2 nanocomposite in aqueous media at room temperature

2018 ◽  
Vol 73 (9) ◽  
pp. 641-645 ◽  
Author(s):  
Sepehr Sadegh-Samiei ◽  
Shahrzad Abdolmohammadi
Keyword(s):  
Heterogeneous Catalyst ◽  
Carboxylic Acids ◽  
Room Temperature ◽  
Aqueous Media ◽  
Reaction Times ◽  
Molar Ratio ◽  
Efficient Synthesis ◽  
Reaction Conditions ◽  
Moderate Reaction ◽  
Recyclable Heterogeneous Catalyst

AbstractA novel and efficient synthesis of eight 5-aryl-1,3-dimethyl-2,4-dioxo-1,2,3,4,5,8-hexahydropyrido[2,3-d]pyrimidine-7-carboxylic acids using a TiO2/SiO2 nanocomposite with a molar ratio of 1:1 as a recyclable heterogeneous catalyst is described. The desired products, five of which are new, are formed in short reaction times (2–3 h) with high to excellent yields (94%–98%) under very moderate reaction conditions (room temperature, aqueous media).

Heterobimetallische 3d-4f-Komplexe mit Bis(1,2-dithiooxalato)nickelat(II) als planarem Brückenbaustein / Heterobimetallic 3d-4f-Complexes with Bis(1,2-dithiooxalato)nickelate(II) as Planar Bridging Block

2005 ◽  
Vol 60 (11) ◽  
pp. 1149-1157 ◽  
Author(s):  
Matthias Siebold ◽  
Alexandra Kelling ◽  
Uwe Schilde ◽  
Peter Strauch
Keyword(s):  
Room Temperature ◽  
Magnetic Moments ◽  
Lanthanide Ions ◽  
Water Molecules ◽  
Unit Cell Parameters ◽  
Ionic Radii ◽  
X Ray ◽  
Cell Parameters ◽  
Heterobimetallic Complexes ◽  
The Individual

Planar bis(1,2-dithiooxalato)nickelates(II) react in aqueous solutions of lanthanide ions to form pentanuclear, heterobimetallic complexes of the general composition [{Ln(H2O)n}2- {Ni(dto)2}3]・xH2O (Ln = Y3+, La3+, Ce3+, Pr3+, Nd3+, Sm3+, Eu3+, Gd3+, Tb3+, Dy3+, Ho3+, Er3+, Tm3+, Yb3+, Lu3+; n = 4 or 5; x = 9 - 12). With [{Nd(H2O)5}2{Ni(S2C2O2)2}3]・xH2O (x = 10 - 12) (1) and [{Er(H2O)4}2{Ni(S2C2O2)2}3]・xH2O (x = 9 - 10) (2) we were able to isolate two complexes of this series as single crystals, which were characterized by X-ray structure analysis. Depending on the individual ionic radii of the lanthanide ions, the compounds crystallize in two different crystal systems with the following unit cell parameters: 1, monoclinic in P21/c with a = 11.3987(13), b = 11.4878(8), c = 20.823(2) Å , β = 98.907(9)° and Z = 2; 2, triclinic in P1̅ with a = 10.5091(6), b = 11.0604(6), c = 11.2823(6) Å , α = 107.899(4)°, β = 91.436(4)°, γ = 112.918(4)° and Z = 1. The channels and cavities appearing in the packing of the molecules are occupied by uncoordinated water molecules. High magnetic moments up to 14.65 BM./f.u. have been observed at room temperature due to the combined moments of the individual lanthanide ions.

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