scholarly journals Synthesis and Molecular Structure of tert-Butyl 3-oxo-2-oxa-5-azabicyclo[2.2.2]octane-5-carboxylate

2014 ◽  
Vol 2014 ◽  
pp. 1-6 ◽  
Author(s):  
Tetsuji Moriguchi ◽  
Suvratha Krishnamurthy ◽  
Toru Arai ◽  
Taisuke Matsumoto ◽  
Koji Araki ◽  
...  
Keyword(s):  
Molecular Structure ◽  
Mass Spectrometry ◽  
High Resolution Mass Spectrometry ◽  
Amino Acid Ester ◽  
Piperidine Ring ◽  
Monoclinic Space Group ◽  
X Ray Diffraction ◽  
X Ray ◽  
H Nmr ◽  
Resolution Mass

The compound tert-butyl 3-oxo-2-oxa-5-azabicyclo[2.2.2]octane-5-carboxylate was synthesized as a cyclic amino acid ester from the corresponding ethyl 2-amino-4-(2-oxiranyl)butanoate HCl salt via an intramolecular lactonization reaction and was characterized by using 1H NMR spectroscopy and high-resolution mass spectrometry. The product was then recrystallized from dichloromethane/diethyl ether and its structure was determined via single crystal X-ray diffraction analysis. The crystal was found to be of the monoclinic space group P21/c (no. 14) with a = 10.217(2) Å, b = 11.676(3) Å, c = 10.273(3) Å, β = 114.186(13)°, and Dcalc = 1.350 g/cm3 at 123 K. The compound has bicyclo[2.2.2]octane structure including a lactone moiety and a piperidine ring, and the two diastereomers of the molecules are present in a 1 : 1 ratio in the crystal.

Improved Access to 1,8-Dichloro-10-(ethynyl)anthracene: A Useful Building Block for (Semi-)rigid Organic Frameworks

Synthesis ◽  
2018 ◽  
Vol 50 (10) ◽  
pp. 2009-2018
Author(s):  
Jan-Hendrik Lamm ◽  
Philipp Niermeier ◽  
Leif Körte ◽  
Beate Neumann ◽  
Hans-Georg Stammler ◽  
...  
Keyword(s):  
Mass Spectrometry ◽  
Building Block ◽  
High Resolution Mass Spectrometry ◽  
Cross Coupling ◽  
Easy Access ◽  
Coupling Reactions ◽  
X Ray Diffraction ◽  
X Ray ◽  
Cross Coupling Reactions ◽  
Resolution Mass

An easy access to 1,8-dichloro-10-(ethynyl)anthracene is reported, which is widely applicable for building up rigid linkers between two 1,8-dichloroanthracene units. For this, 1,8-dichloroanthren-10(9H)-one was reacted with ethynylmagnesium bromide in the presence of CeCl3; the yield was 65%. This building block was used as a substrate in (cross-)coupling reactions and some examples of linked 1,8-dichloroanthracen-10-yls (e.g., 1,8-bis[(1,8-dichloroanthracen-10-yl)-ethynyl]naphthalene or 1,2-bis[(1,8-dichloroanthracen-10-yl)ethynyl]-benzene) were synthesized in good to moderate yields. Linked 1,8-dichloroanthracen-10-yl derivatives were also synthesized by cross-coupling reactions using 10-bromo-1,8-dichloroanthracene and doubly ethynyl-substituted substrates. Linkers between the 1,8-dichloroanthracene units were: butadiynediyl, dimethylsilyldiethynyl, octa-1,7-diyne-1,8-diyl, propane-1,3-diylbis(dimethylsilyl)diethynyl, benzene-1,2-diethynyl, naphthalene-1,8-diyldiethynyl, and anthracene-1,8-diyldiethynyl. The new anthracene compounds were characterized by NMR spectroscopy, high-resolution mass spectrometry, and, in part, by X-ray diffraction experiments.

scholarly journals Synthesis and Molecular Structure of 4′,9′,4″,9″-Tetra-tert-butyl-1′,6′,1″,6″-tetramethoxy-2,5-dioxa[3.3]metabiphenylophane

2014 ◽  
Vol 2014 ◽  
pp. 1-7 ◽  
Author(s):  
Tetsuji Moriguchi ◽  
Tatsuya Egami ◽  
Akihiko Tsuge
Keyword(s):  
Molecular Structure ◽  
Condensation Reaction ◽  
Solvent Molecule ◽  
Dihedral Angles ◽  
Monoclinic Space Group ◽  
X Ray Diffraction ◽  
X Ray ◽  
Cell Parameters ◽  
H Nmr ◽  
Crystal Space

A large calixarene-like metacyclophane, 4′,9′,4″,9″-tetra-tert-butyl-1′,6′,1″,6″-tetramethoxy-2,5-dioxa[3.3]metabiphenylophane, was synthesized by an intermolecular condensation reaction of its corresponding bischloromethyl-biphenyl and bishydroxymethyl-biphenyl precursors. After molecular characterization by 1H NMR spectroscopy and mass spectrometry, the compound generated single crystals by recrystallization from a dichloromethane/hexane mixture, facilitating an exact conformational determination via X-ray diffraction analysis. The crystal was found to belong to the monoclinic space group P21/n with cell parameters a = 19.908(2) Å, b = 9.7193(11) Å, c = 23.350(3) Å, β = 109.594(1)°, and Dcalc=1.150 g/cm3 at 90 K. The compound adopted quite strained 1,2-alternate-like conformations because its biphenyl parts displayed large dihedral angles and rigidity. The crystal did not incorporate any solvent molecule but its molecular cavity and crystal space were effectively filled by the substituents.

Structural Identification of Products from the Chloromethylation of Salicylaldehyde

Synlett ◽  
2018 ◽  
Vol 30 (01) ◽  
pp. 44-48 ◽  
Author(s):  
Muhammad Bala ◽  
Ebrahim Kadwa ◽  
Holger Friedrich
Keyword(s):  
Mass Spectrometry ◽  
Nmr Spectroscopy ◽  
High Resolution Mass Spectrometry ◽  
Structural Identification ◽  
Spectroscopic Techniques ◽  
X Ray Diffraction ◽  
X Ray ◽  
Multinuclear Nmr Spectroscopy ◽  
Ir Spectroscopic ◽  
Resolution Mass

In the functionalization of salicylaldehyde to give 5-(chloromethyl)salicylaldehyde, two byproducts [5-(hydroxymethyl)salicylaldehyde and 5,5′-methylenebis(salicylaldehyde)] were also isolated. ­Detailed characterizations and structural analyses of all three products by single-crystal X-ray diffraction, multinuclear NMR spectroscopy, high-resolution mass spectrometry, and IR spectroscopic techniques are presented and discussed. A strategy is presented for the preferential isolation of the two byproducts through column chromatography.

Two Propanediurea-based Cucurbituril Analogues: Bis-ns-TD[8] and NH-ns-TD[4]

Synlett ◽  
2018 ◽  
Vol 29 (18) ◽  
pp. 2381-2384
Author(s):  
Qiaochun Wang ◽  
Chunhua Dai ◽  
Yenan Shen
Keyword(s):  
Mass Spectrometry ◽  
1H Nmr Spectroscopy ◽  
High Resolution Mass Spectrometry ◽  
The Other ◽  
Amine Group ◽  
X Ray Diffraction ◽  
Excellent Thermal Stability ◽  
X Ray ◽  
Secondary Amine Group ◽  
Resolution Mass

Two new cucurbituril members, one containing two equivalent cavities and the other having an active secondary amine group, were synthesized by condensation of propanediurea (2,4,6,8-tetraazabicyclo[3.3.1]nonane-3,7-dione) with formaldehyde. These two macrocycles exhibit excellent thermal stability, and their structures were confirmed by single-crystal X-ray diffraction, 1H NMR spectroscopy, and high-resolution mass spectrometry.

scholarly journals Synthesis and Molecular Structure of Chiral (2S, 5S)-tert-Butyl 3-Oxo-2-oxa-5-azabicyclo[2.2.2]octane-5-carboxylate

2014 ◽  
Vol 2014 ◽  
pp. 1-6
Author(s):  
Tetsuji Moriguchi ◽  
Suvratha Krishnamurthy ◽  
Toru Arai ◽  
Akihiko Tsuge
Keyword(s):  
Single Crystal ◽  
High Resolution Mass Spectrometry ◽  
Amino Acid Ester ◽  
Ethyl Esters ◽  
X Ray Diffraction ◽  
Chiral Column ◽  
Orthorhombic Space Group ◽  
Chiral Compound ◽  
X Ray ◽  
H Nmr

The title compound (2S, 5S)-tert-butyl 3-oxo-2-oxa-5-azabicyclo[2.2.2]octane-5-carboxylate was synthesized as a chiral cyclic amino acid ester from the corresponding cis- and trans-5-hydroxypipecolic acid ethyl esters via an intramolecular lactonization reaction without using chiral catalyst or enzyme and without separation by chiral column chromatography. The chiral compound was characterized using 1H NMR spectroscopy and high-resolution mass spectrometry. Its exact structure was then determined via single crystal X-ray diffraction analysis of a single crystal obtained after recrystallization of the compound from ethyl acetate/diethyl ether. The crystal was found to be of the orthorhombic space group P212121 (No. 19, noncentrosymmetric, chiral) with a=9.6402(10) Å, b=9.7026(10) Å, c=12.2155(12) Å, Dcalc=1.3194 g/cm3, and a Flack parameter of 0.0(5) at 90 K. The compound has a bicyclo[2.2.2]octane structure comprised of lactone and piperidine groups.

Synthesis and characterization of meso-to-meso directly linked porphyrin-diazaporphyrin triads

2018 ◽  
Vol 22 (09n10) ◽  
pp. 814-820
Author(s):  
Yingying Jia ◽  
Ling Xu ◽  
Bangshao Yin ◽  
Mingbo Zhou ◽  
Jianxin Song
Keyword(s):  
Nickel Complex ◽  
High Resolution Mass Spectrometry ◽  
Dihedral Angles ◽  
X Ray Diffraction ◽  
Extinction Coefficients ◽  
X Ray ◽  
H Nmr ◽  
First Time ◽  
Molar Extinction Coefficients

Beginning with 5,10,15-triarylporphyrin-nickel complex, five meso-to-meso directly linked porphyrin-diazaporphyrin triads were successfully prepared for the first time through a series of reactions including formylation via Vilsmeier–Haack reaction, condensation with pyrrole, bromination with [Formula: see text]-Bromosuccinimide (NBS), oxidation with 2,3-dichloro-5,6-dicyano-1,4-benzoquinone (DDQ), metal-templated cyclization of dibromodipyrrin-metal complexes with NaN[Formula: see text] and demetalization. All these triads were comprehensively characterized by [Formula: see text]H NMR, high-resolution mass spectrometry and UV-vis absorption. In addition, the structure of compound 6Ni was unambiguously determined by X-ray diffraction analysis, which showed that the two dihedral angles are both 86.65 (4)[Formula: see text] between each mean plane of porphyrin and that of central diazaporphyrin The UV-vis absorption spectra disclosed that the longest wavelengths of Soret bands and Q bands for these triads were observed at 429 and 642 nm, respectively. In contrast to diazaporphyrin-porphyrin dyads, diazaporphyrin dimers and diazaporphyrin monomers reported previously the molar extinction coefficients, particularly for triad 8Ni are much higher.

scholarly journals 2.2.5.5-Tetraorganyl-1.4-dioxa-2.5-disilacyclohexane/2,2,5,5-Tetraorganyl-1,4-dioxa-2,5-disilacyclohexanes

1983 ◽  
Vol 38 (2) ◽  
pp. 190-193 ◽  
Author(s):  
Reinhold Tacke ◽  
Hartwig Lange ◽  
Anke Bentlage ◽  
William S. Sheldrick ◽  
Ludger Ernst
Keyword(s):  
Molecular Structure ◽  
Mass Spectrometry ◽  
Diffraction Analysis ◽  
X Ray Diffraction ◽  
X Ray ◽  
Elemental Analyses

Abstract The 2,2,5,5-tetraorganyl-1,4-dioxa-2,5-disilacyclohexanes 2a-2c were prepared by condensation of the corresponding (hydroxymethyl)diorganylsilanes 1 a-1 c. The constitution of the heterocycles was confirmed by elemental analyses, cryoscopic measurements, mass spectrometry, and NMR-spectroscopic (1H, 13C) investigations. The molecular structure of 2 b was determined by X-ray diffraction analysis.

scholarly journals Chloro- and BF2bdk-substituted dithienylethene: Synthesis, photophysical properties, and optical switching behavior

2020 ◽  
pp. 174751982095141
Author(s):  
Zhiqiang Lu ◽  
Wenbo Yang ◽  
Yanhui Bai ◽  
Mo Wang ◽  
Zixu Li ◽  
...  
Keyword(s):  
Mass Spectrometry ◽  
Optical Switching ◽  
High Resolution Mass Spectrometry ◽  
Photophysical Properties ◽  
Red Light ◽  
Switching Behavior ◽  
Polar Solvents ◽  
H Nmr ◽  
Resolution Mass ◽  
C Nmr

A novel chloro- and BF2bdk-substituted dithienylethene derivative, in which a chlorine atom and a difluoroboron β-diketonate (BF2bdk) group are appended at the termini of the dithienylethene core, is developed. The structure was confirmed by 1H NMR, 13C NMR, and high-resolution mass spectrometry (electrospray ionization). It displayed solvent-dependent photophysical properties, and blue/red light-triggered optical switching behavior in nonpolar or less polar solvents.

The crystal structure of dibutyl-bis(pentamethylenedithiocarbamato)tin(IV)

1986 ◽  
Vol 51 (11) ◽  
pp. 2521-2527 ◽  
Author(s):  
Jan Lokaj ◽  
Eleonóra Kellö ◽  
Viktor Kettmann ◽  
Viktor Vrábel ◽  
Vladimír Rattay
Keyword(s):  
Molecular Structure ◽  
Crystal Structure ◽  
Least Squares ◽  
Coordination Polyhedron ◽  
Crystal And Molecular Structure ◽  
Distorted Octahedron ◽  
Monoclinic Space Group ◽  
X Ray Diffraction ◽  
Space Group ◽  
X Ray

The crystal and molecular structure of SnBu2(pmdtc)2 has been solved by X-ray diffraction methods and refined by a block-diagonal least-squares procedure to R = 0.083 for 895 observed reflections. Monoclinic, space group C2, a = 19.893(6), b = 7.773(8), c = 12.947(8) . 10-10 m, β = 129.07(5)°, Z = 2, C20H38N2S4Sn. Measured and calculated densities are Dm = 1.38(2), Dc = 1.36 Mg m-3. Sn atom, placed on the twofold axes, is coordinated with four S atoms in the distances Sn-S 2.966(6) and 2.476(3) . 10-10 m. Coordination polyhedron is a strongly distorted octahedron. Ligand S2CN is planar.

scholarly journals Synthesis of spiro[benzo[4,5]imidazo[2,1-b][1,3]thiazole-2,3-thiolane]s via sulfa-Michael/aldol cascade reactions

2019 ◽  
Vol 43 (1-2) ◽  
pp. 63-66 ◽  
Author(s):  
Jiaying Lei ◽  
Xinliang Fu ◽  
Yulin Huang ◽  
Xiaofang Li
Keyword(s):  
Mass Spectrometry ◽  
Nuclear Magnetic Resonance ◽  
Magnetic Resonance ◽  
High Resolution ◽  
High Resolution Mass Spectrometry ◽  
Cascade Reactions ◽  
Cascade Reaction ◽  
Crystallographic Analysis ◽  
X Ray ◽  
Resolution Mass

The sulfa-Michael/aldol cascade reaction of ( Z)-2-arylmethylidene-benzo[4,5]imidazo[2,1- b]thiazol-3(2H)-ones and 1,4-dithiane-2,5-diol afforded novel 2-aryl-4-hydroxy-spiro[benzo[4,5]imidazo[2,1- b][1,3]thiazole-2,3-thiolan]-3-ones in moderate yields. The structures of all the products were characterized thoroughly by nuclear magnetic resonance, infrared and high-resolution mass spectrometry together with X-ray crystallographic analysis.

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