Coordination compounds of substituted 1,10-Phenanthrolines and related dipyridyls. VII. Complexes of copper(I) and 4,6,4',6'-Tetramethyl-2,2'-bipyridine

A number of diamagnetic complexes of copper(I) and 4,6,4',6'-tetramethyl-2,2'-bipyridine (tmb) have been prepared and some physical properties measured. The complexes of formula Cu(tmb)2X where X = NO3, ClO4, Br, and I behave as 1 : 1 electrolytes in nitrobenzene and nitromethane, while the complex Cu(tmb)2Cl,H2O apparently undergoes partial dissociation in these solvents. All are expected to have a tetrahedral arrangement of the four donor nitrogen atoms about the copper atom. The mono complexes CuXtmb, where X = Cl, Br, and I, appear to be dimeric in the solid state with halogen bridging, but in solution the chloro and bromo complexes rearrange to varying degrees depending on the solvent, forming the salt-type compounds [Cu(tmb)2][CuX2]. CuItmb is insoluble in all common solvents.

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Coordination compounds of substituted 1,10-phenanthrolines and related bipyridyls. XII. Complexes of copper(I), silver(I), and nickel(II) with 2-Methyl-1,10-phenanthroline

Australian Journal of Chemistry ◽

10.1071/ch9700699 ◽

1970 ◽

Vol 23 (4) ◽

pp. 699 ◽

Cited By ~ 15

Author(s):

EW Ainscough ◽

RA Plowman

Keyword(s):

Magnetic Susceptibility ◽

Solid State ◽

Coordination Compounds ◽

Nickel Complexes ◽

Hot Water ◽

Conductivity Measurements ◽

Hypophosphorous Acid ◽

Dimeric Structure ◽

Donor Nitrogen ◽

Reflectance Measurements

Copper(1) salts of the type Cu(mep)2X (X = NO3, ClO4) (mep = 2-methyl- 1,l0-phenanthroline) were obtained by boiling the appropriate bis copper(11) complex in water or by reduction with hypophosphorous acid. They are expected to have a tetrahedral arrangement of donor nitrogen atoms about the copper(1) ion. Complexes Cu(mep)X (X = Br,I) were obtained by reduction of the appropriate copper(11) salt in hot water with hypophosphorous acid. These may be dimeric in the solid state with a tetrahedral arrangement of the ligand donor atoms. Complexes of the type Ag(mep)2X (X = NO3,ClO4) were prepared and are believed to be tetrahedrally coordinated. Ag(mep)Br was also prepared and in the solid state may be a dimeric structure involving the bromo ligand as the bridging unit. Nickel complexes of the type Ni(mep)X2 (X = Cl, NO3) and Ni(mep)2X2,yH2O (X = Cl, y = 4; X = NO3, y = �) were prepared and structures determined as far as possible by means of magnetic susceptibility and conductivity measurements, and by infrared and reflectance measurements.

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Coordination Compounds of Substituted 1,lO-Phenanthrolines and Related Dipyridyls. IV. Physicochemical Study of Complexes of Copper and 2,9-Dimethyl-1,10-phenanthroline

Australian Journal of Chemistry ◽

10.1071/ch9630034 ◽

1963 ◽

Vol 16 (1) ◽

pp. 34 ◽

Cited By ~ 34

Author(s):

JR Hall ◽

NK Marchant ◽

RA Plowman

Keyword(s):

Organic Solvents ◽

Infrared Spectra ◽

Copper Atom ◽

Coordination Compounds ◽

Magnetic Moments ◽

Physicochemical Study ◽

Magnetic Susceptibilities ◽

Donor Nitrogen ◽

Substituted 1

The magnetic susceptibilities, conductivities, and infrared spectra of some complexes of copper and 2,9-dimethyl-1,10-phenanthroline (dmp) have been obtained. The magnetic moments of the copper(II) compounds lie in the range 1.9 to 2.0 B.M. Complexes of formula CudmpX2, where X = NO3, Cl, and Br, are nonelectrolytes in nitrobenzene. The substances Cu(dmp)2X2H2O and hydrated forms of the compounds Cu(dmp)2XClO4, where X = NO3, Cl, and Br behave as 1 : 1 electrolytes. The copper(II) ion in the bis complexes is at least five-coordinate and it is proposed that the donor nitrogen atoms take up a flattened tetrahedral arrangement. The complexes of formula Cu(dmp)2X, where X = NO3, ClO4, Cl, Br. I, and I3 are diamagnetic solids, 1 : 1 electrolytes in nitrobenzene, and are expected to have a tetrahedral arrangement of the four donor nitrogen atoms about the copper atom. The mono complexes CudmpX, where X = Cl, Br, and I are diamagnetic, practically insoluble in organic solvents, and probably dimeric with a tetrahedral arrangement of the ligand donor atoms.

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Improved Sol-Gel Materials for Efficient Solid State Dye Lasers

MRS Proceedings ◽

10.1557/proc-329-279 ◽

1993 ◽

Vol 329 ◽

Cited By ~ 3

Author(s):

Michael Canva ◽

Patrick Georges ◽

Jean-Fran^ois Perelgritz ◽

Alain Brun ◽

Fréddric Chaput ◽

...

Keyword(s):

Solid State ◽

Physical Properties ◽

Room Temperature ◽

Sol Gel ◽

Tunable Lasers ◽

Optical Quality ◽

Dye Lasers ◽

Laser Dyes ◽

Host Matrix ◽

Host Matrices

AbstractPhotoresistant laser dyes were trapped in silica based xerogel host matrices to obtain solid state tunable lasers. For this purpose very dense xerogel samples with improved chemical and physical properties were prepared at room temperature by the sol-gel technology. The as-prepared materials were polished to obtain optical quality surfaces and were used as new lasing media.Lasing action of such different dyes as rhodamine, perylene and pyrromethene doping dense sol-gel matrices was demonstrated. Efficiencies of 30 % or lifetimes of more than 100,000 shots were achieved with different new ≤dye dopant/host matrix≥ couples. Their different performances are reviewed and discussed.

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Formation of di- and polynuclear Mn(II) thiocyanate pyrazole complexes in solution and in the solid state

Zeitschrift für Naturforschung B ◽

10.1515/znb-2018-0104 ◽

2018 ◽

Vol 73 (11) ◽

pp. 793-801

Author(s):

Aleksej Jochim ◽

Christian Näther

Keyword(s):

Solid State ◽

Coordination Compounds ◽

Magnetic Measurements ◽

Metal Cations ◽

Chain Compound ◽

Pyrazole Ligands

AbstractReaction of Mn(NCS)2with pyrazole leads to the formation of three compounds with the compositions Mn(NCS)2(pyrazole)4(1), [Mn(NCS)2]2(pyrazole)6(2) and Mn(NCS)2(pyrazole)2(3). Compound1, already reported in the literature, consists of discrete complexes, in which the Mn(II) cations are octahedrally coordinated by four pyrazole ligands and two terminally N-bonded thiocyanate anions. In compound2each of the two Mn(II) cations are coordinated octahedrally by three pyrazole ligands and one terminal as well as two bridging thiocyanate anions, which link the metal cations into dimers. In compound3also octahedrally coordinated Mn(II) cations are present but they are linked into chainsviacentrosymmetric pairs ofμ-1,3-bridging thiocyanate anions. Upon heating compound1loses the pyrazole co-ligands stepwise and is transformed into the chain compound3viathe dimer2that is formed as an intermediate. Magnetic measurements on compounds2and3reveal dominating antiferromagnetic interactions, as already observed for 1D Mn(NCS)2coordination compounds with pyridine based co-ligands.

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Thermoanalytical Study of Linkage Isomerism in Coordination Compounds. Part 7. A DSC and DFT Investigation of Solid-state Linkage Isomerization in Bis(thiocyanato)-bipyridineplatinum(II) Complex

Zeitschrift für anorganische und allgemeine Chemie ◽

10.1002/zaac.201700198 ◽

2017 ◽

Vol 643 (17) ◽

pp. 1131-1138

Author(s):

Fahime Nasouti ◽

Abbas Eslami

Keyword(s):

Solid State ◽

Coordination Compounds ◽

Thermoanalytical Study ◽

Linkage Isomerism ◽

Linkage Isomerization

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Crosslinking Reaction of Rubber with Aldehydes

Rubber Chemistry and Technology ◽

10.5254/1.3547247 ◽

1970 ◽

Vol 43 (2) ◽

pp. 188-209

Author(s):

Y. Minoura ◽

M. Tsukasa

Keyword(s):

Solid State ◽

Organic Acids ◽

Physical Properties ◽

Lewis Acids ◽

Solid State Reactions ◽

Crosslinking Reaction ◽

Reaction Products ◽

Toluenesulfonic Acid ◽

Ionic Reaction ◽

Acidic Catalysts

Abstract The reactions of rubber with aldehydes have previously been studied in latex or in solutions and the reaction products formed by cyclization, condensation, or addition, have been reported. In the present study, solid-state reactions of rubber with aldehydes were carried out. It was found that crosslinked rubbers may be obtained by press curing in the presence of aldehydes with acidic catalysts. Poly-chloroprene and Hypalon especially undergo these reactions without a catalyst or with a small amount of catalyst. In the experiments using various aldehydes, some improvements in the properties of the crosslinked rubber were observed when aldehydes such as paraformaldehyde or α-polyoxymethylene were used. Some Lewis acids such as SnCl2·2H2O were found to be more effective catalysts than the above, and it was found that organic acids such as p-toluenesulfonic acid could also be used. The curing seemed to be an ionic reaction. The physical properties of the crosslinked rubber are similar to those of sulfur-cured rubbers.

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Synergistic application of continuous granulation and selective laser sintering 3D printing for the development of pharmaceutical dosage forms with enhanced dissolution rates and physical properties

10.1101/2021.02.13.430988 ◽

2021 ◽

Cited By ~ 1

Author(s):

Rishi Thakkar ◽

Yu Zhang ◽

Jiaxiang Zhang ◽

Mohammed Maniruzzaman

Keyword(s):

Solid State ◽

3D Printing ◽

Physical Properties ◽

Dosage Forms ◽

Flow Properties ◽

Printing Process ◽

Powder Bed ◽

Printing Processes ◽

Binder Jetting ◽

Physical Mixtures

AbstractThis study demonstrated the first case of combining novel continuous granulation with powder-based pharmaceutical 3-dimensional (3D) printing processes to enhance the dissolution rate and physical properties of a poorly water-soluble drug. Powder bed fusion (PBF) and binder jetting 3D printing processes have gained much attention in pharmaceutical dosage form manufacturing in recent times. Although powder bed-based 3D printing platforms have been known to face printing and uniformity problems due to the inherent poor flow properties of the pharmaceutical physical mixtures (feedstock). Moreover, techniques such as binder jetting currently do not provide any solubility benefits to active pharmaceutical ingredients (APIs) with poor aqueous solubility (>40% of marketed drugs). For this study, a hot-melt extrusion-based versatile granulation process equipped with UV-Vis process analytical technology (PAT) tools for the in-line monitoring of critical quality attributes (i.e., solid-state) of indomethacin was developed. The collected granules with enhanced flow properties were mixed with vinylpyrrolidone-vinyl acetate copolymer and a conductive excipient for efficient sintering. These mixtures were further characterized for their bulk properties observing an excellent flow and later subjected to a PBF-3D printing process. The physical mixtures, processed granules, and printed tablets were characterized using conventional as well as advanced solid-state characterization. These characterizations revealed the amorphous nature of the drug in the processed granules and printed tablets. Further, the in vitro release testing of the tablets with produced granules as a reference standard depicted a notable solubility advantage (100% drug released in 5 minutes at >pH 6.8) over the pure drug and the physical mixture. Our developed system known as DosePlus combines innovative continuous granulation and PBF-3D printing process which can potentially improve the physical properties of the bulk drug and formulations in comparison to when used in isolation. This process can further find application in continuous manufacturing of granules and additive manufacturing of pharmaceuticals to produce dosage forms with excellent uniformity and solubility advantage.Abstract Figure

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