The influence of water on the spectroscopic properties of a liposoluble magnesium porphyrin

1988 ◽  
Vol 66 (2) ◽  
pp. 273-278 ◽  
Author(s):  
Camille Chapados ◽  
Denis Girard ◽  
Michel Ringuet
Keyword(s):  
Infrared Spectroscopy ◽  
Solid State ◽  
Elemental Analysis ◽  
Spectroscopic Properties ◽  
Infrared Region ◽  
Water Molecules ◽  
Magnesium Atom ◽  
Coordinate Bond ◽  
Influence Of Water

Complexation of water by chlorophyll molecules in natural photosynthetic processes is a matter of great interest. In the present work the influence of water on a model porphyrin, magnesium 2,7,12,17-tetrahexyl-3,8,13,18-tetramethyl porphin (MgTHTMP) has been studied by infrared spectroscopy. A CCl4 (spectroscopic grade) solution of MgTHTMP showed two small bands in the 3600 cm−1 infrared region. These bands are assigned to ν3 and ν1 vibrations of water coordinated to the Mg atom. For MgTHTMP in the solid state, either deposited on an infrared plate or suspended in a Nujol film, none of the OH bands is observed. An elemental analysis confirmed that the solid porphyrin was anhydrous. This evidence indicates that while no water is complexed with MgTHTMP in the solid state, this porphyrin is highly hygroscopic in a CCl4 solution and will easily complex with the few water molecules (less than 0.01%) present in the spectro grade solvent by forming a coordinate bond between the central magnesium atom and the oxygen of water. Several other metallic porphyrins in CCl4 solutions have been studied for comparison with the Mg porphyrin. The spectra of these substances did not show any complexed water. A model of the H2O–MgTHTMP interaction is given and the implication of this model on the aggregation states of chlorophyll will be discussed.

Copper(II) Complexes of a Tripyridyl Ligand: Anion-Dependent Metallosupramolecular Structures

2013 ◽  
Vol 66 (11) ◽  
pp. 1447 ◽  
Author(s):  
James E. M. Lewis ◽  
James D. Crowley
Keyword(s):  
Mass Spectrometry ◽  
Solid State ◽  
Coordination Polymer ◽  
Elemental Analysis ◽  
Spectroscopic Properties ◽  
Nitrate Salt ◽  
X Ray Diffraction ◽  
X Ray ◽  
Salt Structure ◽  
Solid State Structures

A series of copper(ii) complexes of the ligand 2,6-bis(pyridin-3-ylethynyl)pyridine have been synthesised and characterised by 1H and DOSY NMR, IR and UV-Vis spectroscopies, mass spectrometry, elemental analysis and single crystal X-ray diffraction. In solution these systems display almost identical spectroscopic properties, however the solid state structures are shown to vary widely, depending upon the choice of anion. The tetrafluoroborate salt was revealed to be a discrete Cu2L4 cage-like helicate. The tosylate salt, whilst of the same Cu2L4 stoichiometry, was shown to be a coordination polymer. Finally the nitrate salt structure was observed to be a discrete Cu2L2 metallocycle.

scholarly journals Preparation and Thermogravimetric and Antimicrobial Investigation of Cd (II) and Sn (II) Adducts of Mercaptopyridine, Amino Triazole Derivatives, and Mercaptothiazoline Organic Ligand Moieties

2021 ◽  
Vol 2021 ◽  
pp. 1-10
Author(s):  
Ahmed Gaber ◽  
Walaa F. Alsanie ◽  
Robson F. de Farias ◽  
Moamen S. Refat
Keyword(s):  
Infrared Spectroscopy ◽  
Solid State ◽  
Organic Ligand ◽  
Antimicrobial Activities ◽  
Metal Chloride ◽  
Cross Linking ◽  
Water Molecules ◽  
Solid State Route ◽  
Coordination Sites ◽  
Mass Loss Step

The solid adducts of SnCl2.(3amt).H2O, SnCl2.2(3amt).H2O, CdCl2.(3amt), CdCl2.2(3amt), SnCl2.(2mct).0.5H2O, SnCl2.2(2mct), CdCl2.(2mct), CdCl2.2(2mct).H2O, SnCl2.(2mcp).1.5H2O, >2.2(2mcp).4H2O, CdCl2.(2mcp), CdCl2.2(2mcp), SnCl2.(4amt).4H2O, SnCl2.2(4amt).1.5H2O, CdCl2.(4amt).H2O, and CdCl2.2(4amt) (where the 3amt, 4amt, 2mct, and 2mcp represent 3-amino-1,2,4-triazole, 4-amino-1,2,4-triazole, 2-mercaptothiazoline, and 2-mercaptopyridine simple organic chelates, respectively) were prepared using a solid-state route and investigated by CHN elemental analysis and infrared spectroscopy. Additionally, we investigated the thermogravimetric characterization and antimicrobial proprieties. It is verified that for 3amt and 4amt adducts, the coordination occurs through nitrogen atom. For 2mct compounds, the coordination occurs through nitrogen (Sn) or sulfur (Cd). For 2mcp adducts, both coordination sites nitrogen and sulfur are involved. By examination of TG curves, it is confirmed that for each hydrated compounds, the first mass loss step is linked with the release of water molecules followed by the release of ligand molecules and sublimation of the metal chloride. Furthermore, it is verified that, considering only the release of ligand molecules (3amp, 4amp, 2mct, or 2mcp), the cadmium adducts are always more stable than the correspondent tin adducts probably due to the formation of cross-linking bonds in these compounds. Finally, of these 16 adducts, 14 showed antimicrobial activities against different bacterial and fungal strains.

Spectroscopic characterization of silica aerogels prepared using several precursors – effect on the formation of molecular clusters

2017 ◽  
Vol 41 (14) ◽  
pp. 6742-6759 ◽  
Author(s):  
A. Borba ◽  
J. P. Vareda ◽  
L. Durães ◽  
A. Portugal ◽  
P. N. Simões
Keyword(s):  
Fourier Transform ◽  
Infrared Spectroscopy ◽  
Solid State ◽  
Nmr Spectroscopy ◽  
Solid State Nmr ◽  
Spectroscopic Characterization ◽  
Spectroscopic Properties ◽  
Silica Aerogels ◽  
Molecular Clusters

The structural and spectroscopic properties of silica aerogels were studied using complementary approaches, such as Fourier transform infrared spectroscopy and solid-state NMR spectroscopy.

scholarly journals Spectroscopic and Structural Study of a New Conducting Pyrazolium Salt

Molecules ◽  
2021 ◽  
Vol 26 (15) ◽  
pp. 4657
Author(s):  
Sylwia Zięba ◽  
Agata Piotrowska ◽  
Adam Mizera ◽  
Paweł Ławniczak ◽  
Karolina H. Markiewicz ◽  
...  
Keyword(s):  
Hydrogen Bond ◽  
Quantum Theory ◽  
Impedance Spectroscopy ◽  
Spectroscopic Properties ◽  
Hirshfeld Surface ◽  
Structural Defects ◽  
Water Molecules ◽  
Hydrogen Bond Interaction ◽  
Surface Method ◽  
Influence Of Water

The increase in conductivity with temperature in 1H-pyrazol-2-ium 2,6-dicarboxybenzoate monohydrate was analyzed, and the influence of the mobility of the water was discussed in this study. The electric properties of the salt were studied using the impedance spectroscopy method. WB97XD/6-311++G(d,p) calculations were performed, and the quantum theory of atoms in molecules (QTAiM) approach and the Hirshfeld surface method were applied to analyze the hydrogen bond interaction. It was found that temperature influences the spectroscopic properties of pyrazolium salt, particularly the carbonyl and hydroxyl frequencies. The influence of water molecules, connected by three-center hydrogen bonds with co-planar tetrameters, on the formation of structural defects is also discussed in this report.

scholarly journals Synthesis, characterization and thermogravimetric study of Cu(II) adducts with 3- and 4-amino-1,2,4-triazole, 2-mercaptothiazoline and 2-mercaptopyridine

2006 ◽  
Vol 71 (12) ◽  
pp. 1289-1300 ◽  
Author(s):  
Moamen Refat ◽  
Farias de
Keyword(s):  
Infrared Spectroscopy ◽  
Solid State ◽  
Elemental Analysis ◽  
Covalent Character ◽  
Thermogravimetric Study ◽  
Bridging Ligand ◽  
Solid State Route ◽  
Ability To Act ◽  
Metal Ligand ◽  
Ligand Bond

The adducts CuCl2?(3amt), CuCl2?2(3amt)?2H2O, CuCl2?3(3amt), CuCl2?(4amt), CuCl2?2(4amt), CuCl2?3(4amt)?2H2O, CuCl2?(2mct)?H2O, CuCl2?2(2mct)?2.5H2O, CuCl2?3(2mct)?2H2O, CuCl2?(2mcp) and CuCl2?2(2mcp)?H2O, where 3-amino-1,2,4-triazole = 3amt, 4-amino-1,2,4-triazole = 4amt, 2-mercaptothiazoline = 2mct and 2-mercaptopyridine = 2mcp, were synthesized by a solid state route and characterized by CHN elemental analysis and infrared spectroscopy. A thermogravimetric study was also performed. It was verified that 4amp is a molecule with a higher ability to act as a bridging ligand in comparison with 3amp. It was also found that, for all compounds, the mono adducts were the most thermally stable ones. Such a fact is in agreement with a higher ionic and covalent character of the metal-ligand bond in surch compounds. .

Synthesis, Structures and Spectroscopic Properties of 1 : 1 Complexes of Gold(I) Halides with Trimesitylphosphine

2000 ◽  
Vol 53 (3) ◽  
pp. 175 ◽  
Author(s):  
Raymond C. Bott ◽  
Graham A. Bowmaker ◽  
Robbie W. Buckley ◽  
Peter C. Healy ◽  
M. C. Senake Perera
Keyword(s):  
Infrared Spectroscopy ◽  
Solid State ◽  
Far Infrared ◽  
Spectroscopic Properties ◽  
Far Infrared Spectroscopy ◽  
Space Group ◽  
X Ray ◽  
Bond Lengths ◽  
Structure Determinations ◽  
Far Infrared Spectra

Monomeric two-coordinate gold(I) complexes, [Au(P(mes)3)X] (P(mes)3 = tris(2,4,6-trimethylphenyl)phosphine, X = Cl, Br and I), have been prepared and characterized by single-crystal X-ray structure determinations, far-infrared spectroscopy and solution and solid-state CPMAS 31 P n.m.r. spectroscopy. X-Ray structure determinations show that crystals obtained from solutions of [NBu4] [AuX2] and P(mes)3 in acetonitrile for X = Cl, Br and I and in dimethylformamide (dmf) for X = Br and I form an isomorphous series of complexes, crystallizing in space group P21/c with a ª 8, b ª 22, c ª 13 Å, b ª 98˚ (a form). Crystallization of the chloride from dimethylformamide yields the solvated complex [Au(P(mes)3)X]·(dmf) in space group P2/a with a 15.224(2), b 10.070(1), c 18.210(4) Å, b 100.42(2)˚. Electrochemical synthesis of the complexes for X = Cl and Br yield two new crystalline phases; the chloride in space group P21/c with a 10.249(2), b 8.189(2), c 31.844(3) Å, b 91.68(1)˚ (b form) and the bromide in space group Pbca with a 19.208(4), b 15.586(3), c 16.962(4) Å ( g form). The Au–P bond lengths increase in the order Cl < Br < I with distances c. 0.02–0.03 Å longer than average values for other [Au(PR3)X] complexes, reflecting steric congestion by the P(mes)3 ligand. For the unsolvated complexes, the Au–X distances are c. 0.02 Å shorter than average values. For the Cl/dmf solvate, both Au–P and Au–X bond lengths increase. For the a complexes, far-infrared spectra show n(Au 35,37 Cl) 336, 329 cm –1 , n(AuBr) 234 cm –1 and n(AuI) 195 cm –1 and solid-state 31 P CPMAS n.m.r. spectra yield broad peaks with d–3.9 (Cl), –0.6 (Br) and +6.0 I). For the Cl/dmf solvate, n(Au 35,37 Cl) are 334, 327 cm –1 and d is –4.4. Solution 31 P n.m.r. spectra in CDCl3 give sharp single peaks at d –5.0 (Cl), –1.4 (Br) and +5.5 (I) with the similarity of the values with those for the solid-state spectra consistent with similar conformational structures for the [Au(P(mes)3)X] molecules in the two states.

scholarly journals Synthesis, characterization and thermal behaviour of solid state compounds of 4-methoxybenzoate with Manganese, Nickel and Copper

2005 ◽  
Vol 30 (1) ◽  
pp. 15-20 ◽  
Author(s):  
E. C. Rodrigues ◽  
A. C. Vallejo ◽  
E.Y. Ionashiro ◽  
G. Bannach ◽  
M. Ionashiro
Keyword(s):  
Thermal Stability ◽  
Thermal Analysis ◽  
Thermal Decomposition ◽  
Differential Thermal Analysis ◽  
Infrared Spectroscopy ◽  
Solid State ◽  
Thermal Behaviour ◽  
Elemental Analysis ◽  
X Ray

Solid state M-L compounds, where M stands for bivalent Mn, Ni, Cu and L is 4-methoxybenzoate, have been synthesized. Simultaneous thermogravimetry - differential thermal analysis (TG-DTA), X-ray powder diffractometry, infrared spectroscopy, elemental analysis and complexometry were used to characterize and to study the thermal behaviour of these compounds. The results led to information about the composition, dehydration, thermal stability and thermal decomposition of the isolated compounds.

Synthesis, Spectral Properties of Tb (III) Complexes with 2，2'-Dithiosalicylic Acid

2011 ◽  
Vol 366 ◽  
pp. 161-164
Author(s):  
Li Hua Wang
Keyword(s):  
Solid State ◽  
Infrared Spectrum ◽  
Elemental Analysis ◽  
Spectral Properties ◽  
Luminescent Properties ◽  
Water Molecules ◽  
Terbium Complex ◽  
Coordinated Water ◽  
Luminescent Spectra ◽  
Oxygen Atoms

A new terbium complex with aromatic multicarboxylate ligand, 2, 2'-dithiosalicylic acid (L), has been synthesized. The terbium complex was characterized by elemental analysis, infrared spectrum and luminescent spectra, and the complex conforms to 1:1 metal-to-ligand stoichiometry. The complex is stable in air. The results show that the Tb (III) ion in the complex is coordinated by oxygen atoms of the ligand and the oxygen atoms of the nitrate and coordinated water molecules. The luminescent properties of terbium complex have also been investigated in solid state and in organic solvents.

scholarly journals Evaluation of the Molecular State of Piperine in Cyclodextrin Complexes by Near-Infrared Spectroscopy and Solid-State Fluorescence Measurements

2019 ◽  
Vol 2019 ◽  
pp. 1-14
Author(s):  
Toshinari Ezawa ◽  
Yutaka Inoue ◽  
Isamu Murata ◽  
Koichi Takao ◽  
Yoshiaki Sugita ◽  
...  
Keyword(s):  
Infrared Spectroscopy ◽  
Solid State ◽  
Near Infrared ◽  
Molecular State ◽  
The Other ◽  
Water Molecules ◽  
Cyclodextrin Complexes ◽  
Fluorescence Measurements ◽  
Molecular Behavior ◽  
Solid State Fluorescence

The purpose of this study was to evaluate the physicochemical properties of piperine (PP) in ground mixtures (GMs) of PP with α-, β-, or γ-cyclodextrin (CD) under conditions of humidity, heat, and humidity-heat. In solid-state fluorescence measurements, the fluorescence maxima for GM (PP/αCD = 1/2), GM (PP/βCD = 1/1), and GM (PP/γCD = 1/1) were observed at 463, 472, and 469 nm, respectively. On the other hand, the humidified GMs exhibited maxima at 454, 460, and 465 nm, while the humidified-heated samples displayed fluorescence maxima at 455, 455, and 469 nm, respectively. Therefore, the molecular behavior of PP with α, β, and γCD was concluded to vary upon the coordination of water molecules. NIR and solid-state fluorescence measurements revealed that the molecular behavior of PP inside the α, β, and γCD cavity changed by water and heat factors depends on the mobility of the methylenedioxyphenyl group.

Nickel(II)-Tyrosine-and -Tryptophan-Nucleobase Ternary Complexes

1997 ◽  
Vol 52 (11) ◽  
pp. 1325-1330 ◽  
Author(s):  
M. C. Apella ◽  
A. Terron ◽  
J. J. Fiol ◽  
V. Moreno ◽  
E. Molins
Keyword(s):  
Amino Acids ◽  
Infrared Spectroscopy ◽  
Solid State ◽  
Nickel Content ◽  
Ternary Complexes ◽  
Water Soluble ◽  
Water Molecules ◽  
Purine Base ◽  
Ternary Compounds ◽  
Binary Compounds

The interaction between Ni(II) and amino acids with an aromatic residue (such as tyrosine and tryptophan) and either 9 substituted bases or nucleosides has been studied. Ternary derivatives obtained in solid state were characterised by, among other techniques, elemental analysis, thermogravimetry, electronic and infrared spectroscopy. The following complexes have been obtained: 1: [Ni (tyr)2(9EtAde)2] × 4H2O; 2: [Ni (tyr)2(9EtGua)2] × 5H2O; 3: [Ni (tyr)(guo) × 5H2O];4: [Ni (tyr)(ino) × 5H2O];5: [Ni (trp)2(9EtGua)(H2O)] × 2H2O, where tyr is tyrosinate, trp tryptophanate, ino inosinate and guo guanosinate. Thermogrammes are in agreement with the number of water molecules and nickel content (calculated as NiO), together with the ternary nature of these complexes. The binary compounds Ni(tyr)2 × 3H2O and Ni(trp)2 × 3.5H2O were also obtained and the corresponding thermogrammes were registered for comparison purposes. Compounds 1, 2 and5 are water soluble; besides, 1 is fairly soluble in methanol. Compounds 3 and 4 seem to be polymeric. Infrared spectra clearly show the presence of bands either from the amino acid or the base suggesting nickel octahedral coordination through the carboxylic and amino acids groups and a nitrogen from the purine base. These compounds were obtained in water at pH close to 7.0. With other bases such as cytosine and uracil, or their corresponding nucleosides, the same synthesis failed to yield ternary compounds [1,2].

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