scholarly journals Synthesis, Characterisation and Crystal Structure of a Novel Pyridyl Urea Macrocycle

2016 ◽  
Vol 40 (12) ◽  
pp. 753-757
Author(s):  
Shagufta Perveen ◽  
Jeremy D. Kilburn ◽  
Areej M. Al-Taweel ◽  
Mark E. Light
Keyword(s):  
Crystal Structure ◽  
Mass Spectrometry ◽  
Hydrogen Bond ◽  
Nmr Spectroscopy ◽  
Single Crystal ◽  
Structure Determination ◽  
Synthetic Approach ◽  
Pyridyl Nitrogen ◽  
X Ray ◽  
Intramolecular Hydrogen

A novel pyridyl urea based macrocycle has been synthesised and fully characterised including a single crystal X-ray structure determination. The synthetic approach first involves the reaction of benzyloxycarbonylaminopropyl-3-isocyanate with t-butyl 2-[(2-aminopyridin-3-yl)oxy]acetate resulting in a coupling product. After deprotection of the amine and acid moieties and coupling subsequent coupling in the presence of 1-ethyl-3-(3-dimethylaminopropyl)carbodiimide (EDC), a macrocycle is formed. The structures of the compounds were confirmed by mass spectrometry and NMR spectroscopy. The X-ray crystal structure of the macrocycle reveals as expected a non-binding conformation with an intramolecular hydrogen bond between the urea NH and the pyridyl nitrogen.

Synthesis and Single Crystal X-Ray Structure of Ethyl 2-(1,3-Benzoxazol- 2-yl)-5-oxo-3-(4-toluidino)-2,5-dihydro-4-isoxazolecarboxylate

2007 ◽  
Vol 62 (5) ◽  
pp. 705-710 ◽  
Author(s):  
Ali Souldozi ◽  
Jabbar Khalafy ◽  
Ahmad Poursattar Marjani ◽  
Katarzyna Ślepokura ◽  
Tadeusz Lis ◽  
...  
Keyword(s):  
Crystal Structure ◽  
Mass Spectrometry ◽  
Nmr Spectroscopy ◽  
Single Crystal ◽  
Structure Determination ◽  
Single Crystal Structure ◽  
Crystal Structure Determination ◽  
X Ray ◽  
C Nmr

Abstract Ethyl 5-oxo-3-(4-toluidino)-2,5-dihydro-4-isoxazolecarboxylate was prepared from the reaction of diethyl 2-(4-toluidinocarbothioyl)malonate with hydroxylamine. Its reaction with 2- chlorobenzoxazole gave the corresponding N-substituted isoxazolone. The structure of the final product 4 was confirmed by IR, 1H and 13C NMR spectroscopy and mass spectrometry, and by X-ray single crystal structure determination.

First crystal-structure determination of natural lansfordite, MgCO3·5H2O

2017 ◽  
Vol 81 (5) ◽  
pp. 1063-1071 ◽  
Author(s):  
Fabrizio Nestola ◽  
Anatoly V. Kasatkin ◽  
Sergey S. Potapov ◽  
Olga YA. Chervyatsova ◽  
Arianna Lanza
Keyword(s):  
Crystal Structure ◽  
Hydrogen Bond ◽  
Single Crystal ◽  
Structure Determination ◽  
Room Temperature ◽  
Crystal Structure Determination ◽  
Hydrogen Atoms ◽  
Synthetic Analogues ◽  
X Ray

AbstractThis study presents the first crystal-structure determination of natural MgCO3·5H2O, mineral lansfordite, in comparison with previous structural works performed on synthetic analogues. A new prototype single-crystal X-ray diffractometer allowed us to measure an extremely small crystal (i.e. 0.020 mm × 0.010 mm × 0.005 mm) and refine anisotropically all non-hydrogen atoms in the structure and provide a robust hydrogen-bond arrangement. Our new data confirm that natural lansfordite can be stable for several months at room temperature, in contrast with previous works, which reported that such a mineral could be stable only below 10°C.

4-Substituierte 1,3,5,7-Tetramethyl-1,3,5,7-tetraaza-4λ5-phosphaspiro-[3.3]heptan-2,6-dione; Röntgenstrukturanalyse von 1,3,4,6,7,9,10-Heptamethyl-5-oxa-1,3,7,9,10-pentaaza-4 λ5,6 λ5-diphosphadispiro[3.1.3.1]decan-2,8-dion / 4-Substituted 1,3,5,7-Tetramethyl- 1,3,5,7-tetraaza-4λ5-phosphaspiro[3.3]heptane-2,6-diones; Crystal Structure of 1,3,4,6,7,9,10-Heptamethyl-5-oxa-1,3,7,9,10-pentaaza-4λ5,6λ5-diphosphadispiro[3.1.3.1]decane-2,8-dione

1990 ◽  
Vol 45 (10) ◽  
pp. 1407-1415 ◽  
Author(s):  
Johannes Breker ◽  
Peter G. Jones ◽  
Reinhard Schmutzler
Keyword(s):  
Crystal Structure ◽  
Nmr Spectroscopy ◽  
Single Crystal ◽  
Structure Determination ◽  
Spiro Compounds ◽  
The Novel ◽  
Central Ring ◽  
X Ray ◽  
Twofold Axis

The reaction of the tetrachlorophosphoranes RPCl4 (R=Me, Ph) with N,N′-dimethylurea (dmh) (1), or of the diazaphosphetidinone O=C(NMe)2PR (R=CCl3) (3) and chlorine with N,N′-bis(trimethylsilyl)-N,N′-dimethylurea (2) furnished the spiro compounds RP[(NMe)2C=O]2 (7-9). The dichlorophosphoranes O=C(NMe)2PRCl2 (4-6) are intermediates in these reactions; 4 and 6 were isolated but 5 could not be obtained pure. In the reaction of 4 with 2 a mixture of products was formed, from which the novel tricyclic diphosphorane 1,3,4,6,7,9,10-heptamethyl-5-oxa-1,3,7,9,10-pentaaza-4 λ5,6 λ5-diphosphadispiro-[3.1.3.1]decane-2,8-dione (10) was isolated in low yield. Its identity and structure were established by 1H, 13C and 31P NMR spectroscopy and by a single crystal X-ray structure determination, which confirmed the presence of the novel oxazadiphosphetidine ring. 10 crystallizes in C2/c with a = 1321.1(3), b = 687.6(1), c = 1674.5(3) pm, β= 103.30(2)° and Z = 4; R = 0.039 for 1437 unique observed reflections. A crystallographic twofold axis passes through the Me-N···O moiety of the central ring

scholarly journals Synthesis And Single Crystal X-Ray Structure Of 2-(1,3,4-Oxadiazol- 2-yl)Aniline

2007 ◽  
Vol 62 (6) ◽  
pp. 835-840 ◽  
Author(s):  
Ali Souldozi ◽  
Katarzyna Ślepokura ◽  
Tadeusz Lis ◽  
Ali Ramazani
Keyword(s):  
Mass Spectrometry ◽  
Nmr Spectroscopy ◽  
Structural Analysis ◽  
Single Crystal ◽  
Structure Determination ◽  
High Yield ◽  
Aminobenzoic Acid ◽  
Aromatic Rings ◽  
X Ray ◽  
C Nmr

Reaction of 2-aminobenzoic acid with (N-isocyanimino)triphenylphosphorane proceeds smoothly at r. t. to afford 2-(1,3,4-oxadiazol-2-yl)aniline in high yield. The structure of this compound was confirmed by IR, 1H, and 13C NMR spectroscopy, mass spectrometry, and single crystal X-ray structure determination. The X-ray structural analysis of the product indicated that its aromatic rings are approximately co-planar

Dimeres Di(N-lithium–tert–butylamino)bis(dimethylamino)silan - [Si(N(CH3)2)2(NLiC(CH3)3)2]2 – Darstellung und Kristallstruktur / Dimeric Di(N -lithio-tert-butylamino)bis(dimethylamino)silane - [Si(N(CH3)2)2(NLiC(CH3)3)2]2 – Synthesis und Crystal Structure

2001 ◽  
Vol 56 (1) ◽  
pp. 90-94 ◽  
Author(s):  
Josef Engering ◽  
Eva-Maria Peters ◽  
Martin Jansen
Keyword(s):  
Crystal Structure ◽  
Mass Spectrometry ◽  
Solid State ◽  
Nmr Spectroscopy ◽  
Single Crystal ◽  
Title Compound ◽  
Solution Nmr ◽  
X Ray Diffraction ◽  
X Ray ◽  
Solution Nmr Spectroscopy

Abstract [Si(N(CH3)2)2(NLiC(CH3)3)2]2 results from the reaction of silicon tetrachloride with excess terf-butylamine, followed by halogen substitution with LiN(CH3)2, and treatment with n-butyllithium in hexane. The title compound, found to be dimeric in the solid state, was characterised by single crystal X-ray diffraction (triclinic, Pi , a = 10.208(2), b = 12.140(2), c = 15.658(3) Å , a = 79.02(3), ß = 82.80(3), γ = 67.19(3)°, Z = 2, C24H60Li4N8Si2 ), and by solid state and solution NMR-spectroscopy and mass spectrometry.

A Single-Crystal X-Ray Analysis of a Novel Intramolecular Hydrogen-Bonded Biphenyl Phosphorane

1990 ◽  
Vol 43 (4) ◽  
pp. 765 ◽  
Author(s):  
AD Abell ◽  
KB Morris ◽  
V Mckee
Keyword(s):  
Crystal Structure ◽  
Hydrogen Bond ◽  
Single Crystal ◽  
Intramolecular Hydrogen Bond ◽  
Membered Ring ◽  
X Ray ◽  
Intramolecular Hydrogen ◽  
Hydrogen Bonded

An X-ray crystal structure and 1H n.m.r. analysis of the biphenyl phosphorane (4a) has revealed the presence of an intramolecular hydrogen bond resulting in an unusual biphenyl with a bridge forming a nine- membered ring. The related biphenyl phosphorane (4b) exists as two diastereoisomers.

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

Chemistry ◽  
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.

Calcium Carbodiimide Compounds Revisited – Syntheses, Single Crystal Structure Determination and Vibrational Spectra of Ca11N6[CN2]2, Ca4N2[CN2] and Ca[CN2]

2008 ◽  
Vol 63 (5) ◽  
pp. 530-536 ◽  
Author(s):  
Olaf Reckeweg ◽  
Francis J. DiSalvo
Keyword(s):  
Crystal Structure ◽  
Raman Spectrum ◽  
Single Crystal ◽  
Single Crystals ◽  
Vibrational Spectra ◽  
Structure Determination ◽  
X Ray ◽  
Characteristic Features ◽  
Reported Data ◽  
Correct Data

Single crystals of Ca11N6[CN2]2 (dark red needles, tetragonal, P42/mnm (no. 136), a = 1456.22(5), and c = 361.86(2) pm, Z = 2), Ca4N2[CN2] (transparent yellow needles, orthorhombic, Pnma (no. 62), a = 1146.51(11), b = 358.33(4), and c = 1385.77(13) pm, Z = 4) and Ca[CN2] (transparent, colorless, triangular plates, rhombohedral, R3̅m (no. 166), a = 369.00(3), and c = 1477.5(3) pm, Z = 3) were obtained by the reaction of Na2[CN2], CaCl2 and Ca3N2 (if demanded by stoichiometry) in arc-welded Ta ampoules at temperatures between 1200 - 1400 K. Their crystal structures were re-determined by means of single crystal X-ray structure analyses. Additionally, the Raman spectra were recorded on these same single crystals, whereas the IR spectra were obtained with the KBr pellet technique. The title compounds exhibit characteristic features for carbodiimide units with D∞h symmetry (d(C-N) = 121.7 - 123.8 pm and ∡ (N-C-N) = 180°). The vibrational frequencies of these units are in the expected range (Ca11N6[CN2]2: νs = 1230, νs = 2008; δ = 673/645/624 cm−1; Ca4N2[CN2]: νs = 1230, νs = 1986; δ = 672/647 cm−1; Ca[CN2]: νs = 1274, νs = 2031, δ = 668 cm−1). The structural results are more precise than the previously reported data, and with the newly attained Raman spectrum of Ca11N6[CN2]2 we correct data reported earlier.

scholarly journals Synthesis and Complexation Properties of 2-Hydroxy-5-methoxyphenylphosphonic Acid (H3L1). Crystal Structure of the [Cu(H2L1)2(Н2О)2] Complex

2021 ◽  
Vol 91 (11) ◽  
pp. 2176-2186
Author(s):  
G. S. Tsebrikova ◽  
Yu. I. Rogacheva ◽  
I. S. Ivanova ◽  
A. B. Ilyukhin ◽  
V. P. Soloviev ◽  
...  
Keyword(s):  
Crystal Structure ◽  
Hydrogen Bond ◽  
Methoxy Group ◽  
Protonation Constants ◽  
Water Molecules ◽  
X Ray Diffraction ◽  
X Ray ◽  
The Stability ◽  
Intramolecular Hydrogen ◽  
Oxygen Atoms

Abstract 2-Hydroxy-5-methoxyphenylphosphonic acid (H3L1) and the complex [Cu(H2L1)2(H2O)2] were synthesized and characterized by IR spectroscopy, thermogravimetry, and X-ray diffraction analysis. The polyhedron of the copper atom is an axially elongated square bipyramid with oxygen atoms of phenolic and of monodeprotonated phosphonic groups at the base and oxygen atoms of water molecules at the vertices. The protonation constants of the H3L1 acid and the stability constants of its Cu2+ complexes in water were determined by potentiometric titration. The protonation constants of the acid in water are significantly influenced by the intramolecular hydrogen bond and the methoxy group. The H3L1 acid forms complexes CuL‒ and CuL24‒ with Cu2+ in water.

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