444 research outputs found
2,3,6,7,10,11-Hexahydroxytri- phenylene tetrahydrate: a new form of an important starting material for supramolecular chemistry and covalent organic frameworks
In the title compound, C18H12O64H2O, the 2,3,6,7,10,11-hexa- hydroxytriphenylene molecule is located on a twofold axis and two water molecules occupy general positions. The compound forms (4,4) two-dimensional nets via hydrogen bonds between neighbouring hexahydroxytriphenylene molecules, somewhat similar to the cyclopentanone solvates but distinctively different from the monohydrate form. Hydrogen bonds to water molecules connect these layers to form a complicated three-dimensional net, supported also by strong %–% stacking
Olefin-Bond Chemodifferentiation through Cross-Metathesis Reactions: A Stereocontrolled Approach to Functionalized �2,3-Amino Acid Derivatives
catena-Poly[[copper(II)-bis[μ-bis(3,5-dimethyl-1H-pyrazol-4-yl) selenide]] bis(perchlorate)]
In the title compound, {[Cu(C10H14N4Se)2](ClO4)2}n, the CuII ion is located on a twofold rotation axis and has a tetragonally distorted square-planar geometry constituted by four N atoms. A pair of bis(3,5-dimethyl-1H-pyrazol-4-yl) selenide (L) ligands bridges the copper centers into a polymeric chain extending along [001]. The perchlorate anions are involved in intermolecular N—H⋯O hydrogen bonding, which links the chains into layers parallel to the bc plane
3D Printed Palladium Catalyst for Suzuki-Miyaura Cross-coupling Reactions
Selective laser sintering (SLS) 3d printing was utilized to manufacture a solid catalyst for Suzuki-Miyaura cross-coupling reactions from polypropylene as a base material and palladium nanoparticles on silica (SilicaCat Pd(0)R815-100 by SiliCycle) as the catalytically active additive. The 3d printed catalyst showed similar activity to that of the pristine powdery commercial catalyst, but with improved practical recoverability and reduced leaching of palladium into solution. Recycling of the printed catalyst led to increase of the induction period of the reactions, attributed to the pseudo-homogeneous catalysis. The reaction is initiated by oxidative addition of aryl iodide to palladium nanoparticles, resulting in formation of soluble molecular species, which then act as the homogeneous catalyst. SLS 3d printing improves handling, overall practicality and recyclability of the catalyst without altering the chemical behaviour of the active component.Peer reviewe
Angular Regioselective Synthesis of Varied Functionalized Hexahydro-1,2,4-triazolo[4,3-a]quinazolin-9-ones and Their Antiproliferative Action
New 2-thioxopyrimidin-4-ones capable of participating in regioselective reactions with functionally diverse hydrazonoyl chlorides towards angular regioisomers, rather than linear ones, were designed and synthesized to form stereoisomeric cis- and trans-hexahydro [1,2,4]triazolo[4,3-a]quinazolin-9-ones to be tested as antitumor candidates. The angular regiochemistry of the products was verified through crystallographic experiments and NMR studies. In addition, the regioselectivity of the reaction was found to be independent of the stereochemistry of the used 2-thioxopyrimidin-4-one. Only compound 4c demonstrated satisfactory growth inhibition against all the cancer cells used among all the produced drugs
Pseudopeptidic ligands: exploring the self-assembly of isopthaloylbisglycine (H2IBG) and divalent metal ions
No description supplie
catena-Poly[[[trans-diaquabis(pyridine-κN)cobalt(II)]-μ-(4-{N′-[1-(3-acetyl-4-methyl-1H-pyrazol-5-yl)ethylidene]hydrazino}benzoato-κ3 O:N,N′)-[bis(pyridine-κN)cobalt(III)]-μ-(4-{N′-[1-(3-acetyl-4-methyl-1H-pyrazol-5-yl)ethylidene]hydrazino}benzoato-κ3 N,N′:O)]perchlorate 3.66-hydrate]
The title compound, {[Co2(C15H14N4O3)2(C5H5N)4(H2O)2]ClO4·3.66H2O}n, is a one-dimensional coordination polymer, with both CoII and CoIII centres in its structure. The ligand environment surrounding CoIII is formed by two N,N-chelating pyrazole-containing ligands and two pyridine molecules in axial positions. The high-spin CoII ions, situated at crystallographic centres of inversion, exhibit a distorted octahedral coordination mode. The ClO4
− anion is linked to the polymer chain via hydrogen bonds. The chains are connected by hydrogen bonds to produce a three-dimensional structure
cyclo-Tetrakis(μ-3-acetyl-4-methyl-1H-pyrazole-5-carboxylato-κ4 N 2,O 3:N 1,O 5)tetrakis[aquacopper(II)] tetradecahydrate
The title compound, [Cu4(C7H6N2O3)4(H2O)4]·14H2O, a tetranuclear [2 × 2] grid-type complex with S4 symmetry, contains four CuII atoms which are bridged by four pyrazolecarboxylate ligand anions and are additionally bonded to a water molecule. Each CuII atom is coordinated by two O atoms of the carboxylate and acetyl groups, two pyrazole N atoms of doubly deprotonated 3-acetyl-4-methyl-1H-pyrazole-5-carboxylic acid and one O atom of a water molecule. The geometry at each CuII atom is distorted square-pyramidal, with the two N and two O atoms in the equatorial plane and O atoms in the axial positions. O—H⋯O hydrogen-bonding interactions additionally stabilize the structure. One of the uncoordinated water molecules shows half-occupancy
(μ-3-Acetyl-5-carboxylato-4-methylpyrazolido-1:2κ4 N 2,O 3:N 1,O 5)-μ-chlorido-tetrapyridine-1κ2 N,2κ2 N-chlorido-1κCl-dicopper(II) propan-2-ol solvate
The title compound, [Cu2(C7H6N2O3)Cl2(C5H5N)4]·C3H8O, is a binuclear pyrazolate complex, in which the two CuII atoms have different coordination numbers and are connected by a bridging Cl atom. One CuII atom has a distorted square-pyramidal coordination environment formed by two pyridine N atoms, one bridging Cl atom and an N,O-chelating pyrazolate ligand. The other CuII atom adopts an octahedral geometry defined by two pyridine N atoms at the axial positions, two Cl atoms and the coordinated pyrazolate ligand in the equatorial plane. An O—H⋯O hydrogen bond connects the complex molecules and propan-2-ol solvent molecules into pairs. These pairs form columns along the a axis
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