Electron Release and Proton Acceptance Reactions of (dpp-BIAN)Mg(THF)3

(dpp-BIAN)Mg(THF)3 (1) (dpp-BIAN = 1,2-bis[(2,6-diisopropylphenyl)imino]acenaphthene) and (PhCOO)2 react with splitting of the peroxide bridge and formation of the dimeric magnesium benzoate [(dpp-BIAN)MgOCOPh(THF)]2 (2). The reaction of 1 with PhCOOH yields the dimeric magnesium benzoate [(dpp-BIAN)(H)MgOCOPh(THF)]2 (3), whereas 1 and furanyl-2-carboxylic acid react with liberation of hydrogen and formation of (dpp-BIAN)Mg[OCO(2-C4H3O)]2 Mg(dpp-BIAN)(THF) (4). Compounds 2, 3, and 4 have been characterized by elemental analysis, IR spectroscopy, and X-ray structure analysis, compound 3 also by 1H NMR spectroscopy. The eightmembered metallacycles of the centrosymmetric dimers 2 and 3 are almost completely planar. The two magnesium atoms in 4 show different coordination spheres; one is surrounded by its ligands in a trigonal bipyramidal manner, the other one in a tetrahedral fashion. The Mg···Mg separations in 2, 3 and 4 are 4.236, 4.296, and 4.030 Å, respectively

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Synthesis and properties of oxytocin analogues modified in the tripeptide side chain

Collection of Czechoslovak Chemical Communications ◽

10.1135/cccc19840642 ◽

1984 ◽

Vol 49 (3) ◽

pp. 642-652 ◽

Cited By ~ 15

Author(s):

Zdenko Procházka ◽

Michal Lebl ◽

Tomislav Barth ◽

Jan Hlaváček ◽

Antonín Trka ◽

...

Keyword(s):

Nmr Spectroscopy ◽

Carboxylic Acid ◽

Biological Activities ◽

The Other ◽

Side Chain ◽

H Nmr ◽

Fragment Condensation

Two oxytocin analogues were synthesized by fragment condensation (6 + 3) in the presence of dicyclohexylcarbodiimide and 1-hydroxybenzotriazole. In one of the analogues, proline in the position 7 and leucine in the position 8 were substituted by 2-[1-(2-oxo-3-aminopyrrolidinyl)]-4-methylpentanoic acid, in the other proline was replaced by 1-aminocyclopropane-1-carboxylic acid. Biological activities of the first analogue were strongly reduced and dissociation of the uterotonic and galoctogogic activities was observed with both the analogues. The structure of 2-(3-tert-butyloxycarbonylaminopyrrolidin-2-on-1-yl)-4-methylpentanoylglycine and its amide was confirmed by mass and 1 H NMR spectroscopy.

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Liquid crystalline vinylcyclopropane derivatives bearing cholesteryl side groups: synthesis, characterization and polymerization

e-Polymers ◽

10.1515/epoly.2002.2.1.724 ◽

2002 ◽

Vol 2 (1) ◽

Author(s):

Valentina Alupei ◽

Helmut Ritter

Keyword(s):

Phase Transition ◽

Nmr Spectroscopy ◽

Carboxylic Acid ◽

Ir Spectroscopy ◽

Radical Polymerization ◽

Liquid Crystalline ◽

Optically Active ◽

H Nmr

AbstractNew optically active 1,1-disubstituted 2-vinylcyclopropanes ,3a, b were synthesized by esterification of the corresponding 1-ethoxycarbonyl-2-vinylcyclopropane- 1-carboxylic acid 2a,b with cholesterol and characterized by 1H NMR and IR spectroscopy. The liquid crystalline properties of the obtained monomers are reported. The effect of the structure of the 2-vinylcyclopropane monomers on the phase transition of the mesogen was investigated. Radical polymerization of the asymmetrically substituted monomers 3a,b in solution and in bulk resulted in liquidcrystalline polymers with 1,5-opened units, as evidenced by 1H NMR spectroscopy.

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Cycloaddition Reactions of Arylmethylenemalonaldehydes with Olefins

Collection of Czechoslovak Chemical Communications ◽

10.1135/cccc19922337 ◽

1992 ◽

Vol 57 (11) ◽

pp. 2337-2358 ◽

Cited By ~ 4

Author(s):

Dalimil Dvořák ◽

David Šaman ◽

Zdeněk Arnold ◽

Ivana Císařová ◽

Václav Petříček

Keyword(s):

Nmr Spectroscopy ◽

Carboxylic Acid ◽

Vinyl Ether ◽

Aromatic Nucleus ◽

Ethyl Vinyl Ether ◽

Cycloaddition Reactions ◽

Ethyl Vinyl ◽

X Ray ◽

H Nmr ◽

Conformational Equilibria

A series of 2,4-disubstituted 3,4-dihydro-2H-pyran-5-carboxaldehydes II-XIX was prepared by reaction of substituted arylmethylenemalonaldehydes I with 2-methylpropane, 1,1-diphenylethylene, styrene, ethyl vinyl ether, 1,1-dimethoxyethylene and 1,1-bis(methylthio)ethylene. In the case of the reaction with ethyl vinyl ether the dependence of the ratio of the arising cis- and trans- 2-ethoxy-4-aryl-3,4-dihydropyran-5-carboxaldehydes VII-XIV on the substitutent on the aromatic nucleus was studied. Information on the mechanism of this reaction was obtained and conformational equilibria of 2-ethoxy-4-aryl-3,4-dihydropyran-5-carboxaldehydes in solution were studied by 1H NMR spectroscopy. The structure of trans-2-ethoxy-4-(4-chlorophenyl)-3,4-dihydropyran-5-carboxaldehyde (trans-VIII) was confirmed by X-ray analysis of the corresponding carboxylic acid trans-XXII.

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Mixed behavior of p-phenylenediaminium guest binding with the inverted cucurbit[6]uril host

Organic & Biomolecular Chemistry ◽

10.1039/c5ob01074h ◽

2015 ◽

Vol 13 (30) ◽

pp. 8330-8334 ◽

Cited By ~ 7

Author(s):

De-Qing Zhang ◽

Rui-Lian Lin ◽

Wen-Qi Sun ◽

Zhu Tao ◽

Qian-Jian Zhu ◽

...

Keyword(s):

Nmr Spectroscopy ◽

Sandwich Structure ◽

The Other ◽

Binding Interaction ◽

X Ray ◽

X Ray Crystallography ◽

H Nmr ◽

Guest Binding ◽

Different Types ◽

Inclusion Structure

The binding interaction between inverted cucurbit[6]uril (iQ[6]) and p-phenylenediaminium has been investigated by X-ray crystallography, 1H NMR spectroscopy and ITC. Our data indicate that the host and the guest can form two different types of complexes: one is an inclusion structure and the other is a sandwich structure.

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Preparation of anthracene-based tetraperimidine hexafluorophosphate and selective recognition of chromium(III) ions

Beilstein Journal of Organic Chemistry ◽

10.3762/bjoc.15.278 ◽

2019 ◽

Vol 15 ◽

pp. 2847-2855

Author(s):

Qing-Xiang Liu ◽

Feng Yang ◽

Zhi-Xiang Zhao ◽

Shao-Cong Yu ◽

Yue Ding

Keyword(s):

Nmr Spectroscopy ◽

Ir Spectroscopy ◽

Selective Recognition ◽

Addition Compound ◽

X Ray ◽

H Nmr ◽

C Nmr

A novel anthracene-based tetraperimidine hexafluorophosphate 3 was prepared, and its structure was determined through X-ray analysis, HRMS as well as 1H and 13C NMR spectroscopy. In the cationic moiety of 3, two (N-ethylperimidinyl–C2H4)2NCH2– arms were attached to the 9- and 10-positions of anthracene. In addition, compound 3 was used as a chemosensor to research the ability to recognize Cr3+ through fluorescence and UV titrations, HRMS, as well as 1H NMR and IR spectroscopy. The results indicate that 3 is an effective chemosensor for Cr3+.

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Tautomerisation in 1-(4-Methylphenylazo)naphthalen-2-ol and 2-(4-Methylphenylazo)-4-methylphenol: A Crystallographic and 13C{1H}NMR Study

Journal of Chemical Research ◽

10.1177/174751989902300304 ◽

1999 ◽

Vol 23 (3) ◽

pp. 178-179

Author(s):

Wendy I. Cross ◽

Kevin R. Flower ◽

Robin G. Pritchard

Keyword(s):

Acetic Acid ◽

Nmr Spectroscopy ◽

Resonant Frequency ◽

X Ray Diffraction ◽

X Ray ◽

H Nmr ◽

Nmr Study ◽

Acetic Acid Esters ◽

Acid Esters ◽

Equivalent Carbon

The acetic acid esters of 1-(4-methylphenylazo)naphthalen-2-ol 1 and 2-(4-methylphenylazo)-4-methylphenol 3 are prepared and characterised by single crystal X-ray diffraction studies and 13C{1H}NMR spectroscopy; the position of the C(2)13C resonance for the ester is used to predict the position of resonant frequency of the equivalent carbon in the parent alcohols and hence, calculate the position of the azo-hydrazone equilibrium in these compounds.

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Exploring the Structural Chemistry of Pyrophosphoramides: N,N′,N″,N‴-Tetraisopropylpyrophosphoramide

Chemistry ◽

10.3390/chemistry3010013 ◽

2021 ◽

Vol 3 (1) ◽

pp. 149-163

Author(s):

Duncan Micallef ◽

Liana Vella-Zarb ◽

Ulrich Baisch

Keyword(s):

Crystal Structure ◽

Mass Spectrometry ◽

Nuclear Magnetic Resonance ◽

Hydrogen Bonding ◽

Nmr Spectroscopy ◽

Ir Spectroscopy ◽

Room Temperature ◽

Intermolecular Hydrogen Bonding ◽

X Ray Diffraction ◽

X Ray

N,N′,N″,N‴-Tetraisopropylpyrophosphoramide 1 is a pyrophosphoramide with documented butyrylcholinesterase inhibition, a property shared with the more widely studied octamethylphosphoramide (Schradan). Unlike Schradan, 1 is a solid at room temperature making it one of a few known pyrophosphoramide solids. The crystal structure of 1 was determined by single-crystal X-ray diffraction and compared with that of other previously described solid pyrophosphoramides. The pyrophosphoramide discussed in this study was synthesised by reacting iso-propyl amine with pyrophosphoryl tetrachloride under anhydrous conditions. A unique supramolecular motif was observed when compared with previously published pyrophosphoramide structures having two different intermolecular hydrogen bonding synthons. Furthermore, the potential of a wider variety of supramolecular structures in which similar pyrophosphoramides can crystallise was recognised. Proton (1H) and Phosphorus 31 (31P) Nuclear Magnetic Resonance (NMR) spectroscopy, infrared (IR) spectroscopy, mass spectrometry (MS) were carried out to complete the analysis of the compound.

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[Zn(phen)2(CX3COO)]+, X = H orCl; Influence of X on the Coordination Mode of the Carboxylate Group (phen = 1,10-Phenanthroline)

Zeitschrift für Naturforschung B ◽

10.1515/znb-2005-1005 ◽

2005 ◽

Vol 60 (10) ◽

pp. 1049-1053 ◽

Cited By ~ 1

Author(s):

Zeanab Talaei ◽

Ali Morsali ◽

Ali R. Mahjoub

Keyword(s):

Nmr Spectroscopy ◽

Elemental Analysis ◽

Coordination Mode ◽

Bidentate Ligand ◽

Carboxylate Group ◽

X Ray ◽

X Ray Crystallography ◽

H Nmr ◽

Coordinate Geometry ◽

C Nmr

Two new ZnII(phen)2 complexes with trichloroacetate and acetate anions, [Zn(phen)2(CCl3COO)- (H2O)](ClO4) and [Zn(phen)2(CH3COO)](ClO4), have been synthesized and characterized by elemental analysis, IR, 1H NMR, 13C NMR spectroscopy. The single crystal X-ray data of these compounds show the Zn atoms to have six-coordinate geometry. From IR spectra and X-ray crystallography it is established that the coordination of the COO− group is different for trichloroacetate and acetate. The former acts as a monodentate whereas the latter acts as a bidentate ligand.

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Estimating the energy of intramolecular bifurcated (three-centered) hydrogen bond by X-ray, IR and 1 H NMR spectroscopy, and QTAIM calculations

Journal of Molecular Structure ◽

10.1016/j.molstruc.2018.02.106 ◽

2018 ◽

Vol 1163 ◽

pp. 185-196 ◽

Cited By ~ 14

Author(s):

Andrei V. Afonin ◽

Irina V. Sterkhova ◽

Alexander V. Vashchenko ◽

Mark V. Sigalov

Keyword(s):

Hydrogen Bond ◽

Nmr Spectroscopy ◽

X Ray ◽

H Nmr

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Synthesis, Structure, and Properties of a Dinuclear Cu(II) Coordination Polymer Based on Quinoxaline and 3,3-Thiodipropionic Acid Ligands

10.21203/rs.3.rs-209819/v1 ◽

2021 ◽

Author(s):

Adedibu Clement Tella ◽

Samson Owalude ◽

Vincent Adimula ◽

Adetola Oladipo ◽

Victoria Olayemi ◽

...

Keyword(s):

Nmr Spectroscopy ◽

Nitrogen Atom ◽

Coordination Polymer ◽

Elemental Analysis ◽

Catalytic Reduction ◽

Copper Acetate ◽

Structure And Properties ◽

X Ray Diffraction ◽

X Ray ◽

H Nmr

Abstract The coordination polymer [Cu2(TDPH)4(QNX)].DMF, (QNX = Quinoxaline; TDPH = 3,3-thiodipropionic acid), has been prepared by reaction of copper acetate, TDPH, and quinoxaline. The compound was characterized by elemental analysis, FTIR spectroscopy, and single-crystal X-ray diffraction. The crystal is monoclinic with a P21/n space group and dimensions of a = 12.889(3) Å, b = 14.983(4) Å, c = 14.091(3) Å, α = 90 °, β = 90.200(11) °, γ = 90 °, V = 2721.18 (2) Å3, Z = 4. The ligands are hexagonally coordinated to the Cu(II) centre in the form of Cu2O4N with one nitrogen atom from the quinoxaline ligand, and four oxygen atoms from four TDPH molecules in a monodentate fashion. The Cu-Cu bond length was 2.642(1) and 2.629(1) Å for the Cu1----Cu1 and Cu2----Cu2 bonds. The QNX ligand bridged the two copper atoms. The catalytic reduction of 4-nitrophenol to 4-aminophenol using NaBH4 in the presence of [Cu2(TDPH)4(QNX)].DMF, as catalyst was completed within 11 minutes. The 4-aminophenol product was confirmed using 1H NMR spectroscopy.

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