The Chlorination of Some Substituted 2,4-Dimethylphenols

1994 ◽  
Vol 47 (2) ◽  
pp. 289 ◽  
Author(s):  
JLM Gordon ◽  
MP Hartshorn ◽  
RJ Martyn ◽  
AJ Morgan ◽  
WT Robinson ◽  
...  
Keyword(s):  
Crystal Structure ◽  
Acetic Acid ◽  
Carbon Tetrachloride ◽  
Acetic Anhydride ◽  
Methyl Group ◽  
X Ray

Chlorination reactions of 2-chloro-3,4,6-trimethylphenol (4), 2-chloro-4,6-dimethylphenol (5) and 3-chloro-2,4,6-trimethylphenol (6) are described. In acetic acid or acetic anhydride solution, chlorinations yield predominantly the corresponding 4-chlorocyclohexa-2,5-dienones (8), (17a) and (29), but in carbon tetrachloride containing pyridine products are formed which result from the modification of the 4-methyl group in each substrate. X-Ray crystal structure analyses are reported for compounds (7), (14), (28) and (31).

An unusual reaction of a bridged triterpenoid α-diketone with acetic anhydride

1991 ◽  
Vol 56 (12) ◽  
pp. 2917-2935 ◽  
Author(s):  
Eva Klinotová ◽  
Václav Křeček ◽  
Jiří Klinot ◽  
Miloš Buděšínský ◽  
Jaroslav Podlaha ◽  
...  
Keyword(s):  
Acetic Acid ◽  
Nmr Spectroscopy ◽  
Acetic Anhydride ◽  
Spectral Methods ◽  
X Ray Diffraction ◽  
X Ray ◽  
Mild Conditions ◽  
Condensation Products ◽  
Unsaturated Lactones ◽  
C Nmr

3β-Acetoxy-21,22-dioxo-18α,19βH-ursan-28,20β-olide (IIIa) reacts with acetic anhydride in pyridine under very mild conditions affording β-lactone IVa and γ-lactones Va and VIIa as condensation products. On reaction with pyridine, lactones Va and VIIa undergo elimination of acetic acid to give unsaturated lactones VIIIa and IXa, respectively. Similarly, the condensation of 20β,28-epoxy-21,22-dioxo-18α,19βH-ursan-3β-yl acetate (IIIb) with acetic anhydride leads to β-lactone IVb and γ-lactone Vb; the latter on heating with pyridine affords unsaturated lactone VIIIb and 21-methylene-22-ketone Xb. The structure of the obtained compounds was derived using spectral methods, particularly 1H and 13C NMR spectroscopy; structure of lactone IVa was confirmed by X-ray diffraction.

Systhesis, Characterization and Spectroscopic Properties of (2E,6E)-2,6-Bis(2,3,4-tri-methoxy-benzylidene)cyclohexanone

2011 ◽  
Vol 396-398 ◽  
pp. 2338-2341
Author(s):  
Xing Chuan Wei ◽  
Zhi Li Liu ◽  
Kun Zhang ◽  
Zhi Yun Du ◽  
Xi Zheng
Keyword(s):  
Crystal Structure ◽  
Acetic Acid ◽  
Hydrogen Bonds ◽  
Title Compound ◽  
Spectroscopic Properties ◽  
Spectral Studies ◽  
Double Bonds ◽  
X Ray ◽  
Π Interactions ◽  
X Ray Crystallography

In this paper, (2E,6E)-2,6-Bis(2,3,4-tri-methoxy -benzylidene)cyclohexanone (omitted as tmbcho) (1) was obtained by the reaction of acetic acid, tetrahydrofuran, cyclohexanone and 2,3,4-tri-methoxy-benzaldehyde. Three non-classic hydrogen bonds were observed in the compound. X-ray crystallography shows that the crystal structure is stabilized by intermolecular C-H•••π interactions and it contains plenty of conjugated double bonds. The title compound was characterized by UV-vis and fluorescent spectral studies.

4-(Bromomethyl)benzophenone

2007 ◽  
Vol 63 (3) ◽  
pp. o1188-o1189 ◽  
Author(s):  
Wei-Jian Xu ◽  
Yang-Ling Zang ◽  
Guo-Liang Wu ◽  
Sheng-Pei Su ◽  
De-Yue Qiu
Keyword(s):  
Crystal Structure ◽  
Carbon Tetrachloride ◽  
Dihedral Angle ◽  
Structure Analysis ◽  
Title Compound ◽  
Crystal Packing ◽  
Crystal Structure Analysis ◽  
X Ray ◽  
Compound C ◽  
Phenyl Rings

The title compound, C14H11BrO, was synthesized by the reaction of 4-methylbenzophenone and bromine in carbon tetrachloride. X-ray crystal structure analysis reveals that the benzene and phenyl rings form a dihedral angle of 59.53 (6)°, and the crystal packing is stabilized by intermolecular C—H...π interactions.

The Meisenheimer rearrangement in heterocyclic synthesis. II. Synthesis and X-ray crystal structure of a tetrahydro-1H-2,3-benzoxazocine and preparation of a hexahydro-2,3-benzoxazonine

1980 ◽  
Vol 33 (6) ◽  
pp. 1323 ◽  
Author(s):  
JB Bremner ◽  
EJ Browne ◽  
PE Davies ◽  
CLWAH Raston
Keyword(s):  
Molecular Structure ◽  
Crystal Structure ◽  
Acetic Acid ◽  
Crystal And Molecular Structure ◽  
Phosphorus Oxychloride ◽  
Crystallographic Analysis ◽  
Heterocyclic Synthesis ◽  
Reaction Conditions ◽  
X Ray ◽  
Heterocyclic Derivatives

The heterocyclic derivatives, 8,9-dimethoxy-3-methyl-1-phenyl-3,4,5,6- tetrahydro-1H-2,3-benzoxazocine(3a) and 9,10-dimethoxy-3-methyl-1- phenyl-1,3,4,5,6,7-hexahydro-2,3-benzoxazonine (3b),examples of two new ring systems, have been prepared by Meisenheimer rearrangement of the corresponding 2-benzazepine and 2-benzazocine N-oxide derivatives (2a) and (2b). The Bischler-Napieralski-type cyclization reaction was used in the preparation of the tertiary amine precursors of these N-oxides reaction conditions for the cyclization were critical and phosphorus oxychloride in refluxing butanenitrile was found to give the best yields of the seven- or eight-membered cyclic imine intermediates. Reductive cleavage of the benzoxazocine derivative (3a) with zinc in acetic acid followed by N-methylation gave the expected product, [2-{3- (dimethylamino)propyl}-4,5-di-methoxyphenyl]phenylmethanol (12). The crystal and molecular structure of (3a) has been determined by X-ray crystallographic analysis.

Synthesis, Characterization, and Crystal Structure of Several Novel Acidic Ionic Liquids: 1-ethyl-2-alkyl-benzimidazolium Tetra-Fluoroborate

2013 ◽  
Vol 457-458 ◽  
pp. 139-143 ◽  
Author(s):  
Ming Tian Wang ◽  
Chang Ping Pan ◽  
Wei Peng Gai ◽  
Xiao Xia Lv ◽  
Min Gang Zhai ◽  
...  
Keyword(s):  
Crystal Structure ◽  
Ionic Liquid ◽  
Acetic Acid ◽  
Catalytic Activity ◽  
Lamellar Structure ◽  
X Ray Diffraction ◽  
X Ray ◽  
Acidic Ionic Liquid ◽  
Acidic Ionic Liquids ◽  
Good Catalytic Activity

A series of novel acidic ionic liquid: 1-ethyl-2-alkyl-benzimidazolium tetra-fluoroborate (alkyl= Et, Pr-n, Bu-n) were prepared by simple acid-based neutralization of 1-ethyl-2-alkyl-benzimidazole and tetrafluoroboric acid. The compounds were characterized by FTIR spectra, elemental analysis,1HNMR spectra and thermogravimetric analysis. These novel tetra-fluoroborate salts show good catalytic activity to esterification of benzyl alcohol and acetic acid. Furthermore, a crystal of ([H-ebBiBF4) was prepared with the crystal structure and determined by X-ray diffraction analysis. The molecular is of lamellar structure as mainly π electron ring is stacked interleaving between two layers. The results of cation and anion arranged orderly in pair indicate that the coulombic attraction is more dominant. Simultaneously, the weak local hydrogen bonds C-H···F exist in the molecules.

Effects of solvents on the crystal structure of cross-linked lysozyme crystals

2018 ◽  
Vol 32 (19) ◽  
pp. 1840041
Author(s):  
Yohei Yamada ◽  
Shota Toyama ◽  
Tomoki Yabutani
Keyword(s):  
Crystal Structure ◽  
Acetic Acid ◽  
Hydrochloric Acid ◽  
Dimethyl Sulfoxide ◽  
Optical Microscopy ◽  
Immersion Test ◽  
X Ray ◽  
Lattice Constants ◽  
X Ray Crystallography ◽  
Lysozyme Crystals

The effects of solvents on the structural stability of cross-linked lysozyme crystals were investigated by an immersion test using alkaline (0.1 M ammonia [NH3] and 0.1 M sodium hydroxide [NaOH]), acidic (0.1 M acetic acid [CH3COOH] and 0.1 M hydrochloric acid [HCl]) and organic (50% [v/v] and undiluted ethanol, acetone, 2-propanol and dimethyl sulfoxide [DMSO]) solvents. The morphology and lattice constants were monitored by optical microscopy and X-ray crystallography. The cross-linked crystals exhibited good stability against NH3, CH3COOH, HCl, ethanol, acetone and 2-propanol. However, samples preserved in DMSO and NaOH were severely degraded.

The crystal structure of 5-O-Acetyl-1,2 : 3,4-di-O-isopropylidene-α-D-glucoseptanose, C14H22O7, by use of X-ray and neutrondiffraction data

1983 ◽  
Vol 36 (11) ◽  
pp. 2269 ◽  
Author(s):  
RA Wood ◽  
VJ James ◽  
AD Rae ◽  
JD Stevens ◽  
FH Moore
Keyword(s):  
Crystal Structure ◽  
Neutron Diffraction ◽  
Diffraction Analysis ◽  
Chair Conformation ◽  
Asymmetric Unit ◽  
Methyl Group ◽  
Neutron Diffraction Analysis ◽  
X Ray ◽  
Acetate Methyl ◽  
Independent Molecules

The crystal structure of 5-O-acetyl-1,2:3,4-di-O-isopropylidene-α-D-glucoseptanose [P212121, Z 8, a 14.329(5), b 22.075(5), c 10.012(5) �] has been determined by X-ray and neutron diffraction analyses. For the neutron diffraction analysis, the acetate group and the trans-O-isopropylidene group were deuterated. Constrained refinement was used in the neutron diffraction analysis to counter over parameterization in the block-diagonal least-squares refinement. Final unweighted R-values were 0.038 [X-ray for 3070 reflections with [Fo > 2.58σ (Fo)] and 0.061 [neutron for 1118 reflections with Fo > 4σ ([Fo)]The neutron refinement revealed a disordering of the acetate methyl group in each of the two independent molecules in the asymmetric unit. The septanose ring in each molecule adopted the same twist-chair conformation but the dioxolan rings assumed different twist and envelope conformations.

Molecular Cocrystals of Carboxylic Acids. XVII. Spectral Characterization of the Adducts of Triphenylphosphine Oxide With Substituted Phenoxyacetic Acids and the Crystal Structure of the 1 : 1 Adduct With (4-Chloro-2-methylphenoxy)acetic Acid

1994 ◽  
Vol 47 (7) ◽  
pp. 1401 ◽  
Author(s):  
DE Lynch ◽  
G Smith ◽  
KA Byriel ◽  
CHL Kennard ◽  
AK Whittaker ◽  
...  
Keyword(s):  
Crystal Structure ◽  
Acetic Acid ◽  
Triphenylphosphine Oxide ◽  
X Ray Diffraction ◽  
X Ray ◽  
Acid Proton ◽  
Phosphoryl Oxygen ◽  
Phenoxyacetic Acids ◽  
Dichlorophenoxy Acetic Acid ◽  
Molecular Adducts

A series of 1:1 molecular adducts of triphenylphosphine oxide ( tppo ) with substituted phenoxyacetic acids has been prepared and characterized by using infrared, solid-state 1H and 31P n.m.r. spectroscopy, and X-ray powder diffraction methods. The crystal structure of one of these, with the herbicidally active (4-chloro-2-methylphenoxy)acetic acid ( mcpa ),[( tppo )( mcpa )], has been determined by X-ray diffraction methods. This compound is isomorphous with the tppo adduct of (2,4-dichlorophenoxy)acetic acid. The title compound has two independent and different molecular adducts in the asymmetric unit each with strong hydrogen-bonding interactions between the carboxylic acid proton and the phosphoryl oxygen of tppo [O...O, 2.579, 2.647(9)Ǻ].

Structure Investigations of Agonists of the Natural Neurotransmitter Acetylcholine VI [1]. X-Ray Structure Analysis of Trimethyl[2-(propionyloxy)ethyl]- ammonium-iodide (O-Propionylcholine-iodide)

1986 ◽  
Vol 41 (5-6) ◽  
pp. 641-646 ◽  
Author(s):  
Alfred Gieren ◽  
Michail Kokkinidis
Keyword(s):  
Crystal Structure ◽  
Nitrogen Atom ◽  
Formula Unit ◽  
Ammonium Iodide ◽  
Asymmetric Unit ◽  
Torsion Angles ◽  
Methyl Group ◽  
X Ray ◽  
Acetylcholine Chloride ◽  
Structure Investigations

The title compound (1) crystallizes in the orthorhombic, noncentrosymmetric space group Pna21 with a = 10.241(11), b = 12.903(12), c = 9.312(9) Å and with one formula unit per asymmetric unit. The stereochemically comparable torsion angles of the cation of 1 and of acetylcholine chloride are analogous. In the crystal structure the trimethylammonio methyl group is surrounded by three anions in the first coordination sphere. The geometry of a triangle formed by one of these counterions which occupies a special face of the N+C4 tetrahedron of the (CH3)3N+-CH2-R moiety, the nitrogen atom of the ammonium group and the oxygen atom of the carbonyl group is typical for nicotinic agonists.

Preparation and Crystal Structure of the Potentially Tridentate Substituted Phenoxyacetic Acid (2-Benzoyl-5-methoxyphenoxy)acetic Acid and Its Complex Adduct With Sodium

1995 ◽  
Vol 48 (4) ◽  
pp. 869 ◽  
Author(s):  
G Smith ◽  
EJ Oreilly ◽  
SA See ◽  
KA Byriel ◽  
CHL Kennard
Keyword(s):  
Crystal Structure ◽  
Acetic Acid ◽  
Carboxy Group ◽  
Intramolecular Hydrogen Bonding ◽  
Ligand Molecule ◽  
Phenoxyacetic Acid ◽  
X Ray Diffraction ◽  
X Ray ◽  
Intramolecular Hydrogen ◽  
Hydrogen Bonded

The ring-substituted phenoxyacetic acid (2-benzoyl-5-methoxyphenoxy)acetic acid (HL) (3) and its complex adduct dimer (4) with sodium, [Na2(L)2(HL)2].2HL, have been synthesized and their structures determined by X-ray diffraction. The acid (3) does not have the usual cyclic hydrogen-bonded dimer association, but instead has three-centre intramolecular hydrogen bonding between the carboxyl proton and both the ether and keto oxygens [O---O, 2.602(3), 2.711(3) Ǻ respectively]. Each sodium in the centrosymmetric complex dimer (4) is seven-coordinate [Na-O, 2.313(5)-2.612(5) Ǻ], involving the 'inner' three oxygens of both a protonated and an ionic ligand molecule. In addition, one of these carboxyl oxygens forms a bridge to the inversion-related sodium, while the uncoordinated carboxyl oxygen is hydrogen-bonded to a protonated carboxy group [O---O, 2.464(8) Ǻ]. The molecules of the lattice acid have only one hydrogen-bonded association with the second uncoordinated carboxy group in the dimer [O---O, 2.513(7) Ǻ].

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