Structure reexamination of aliphatic nitrones and their dimers

1979 ◽  
Vol 44 (7) ◽  
pp. 2221-2229 ◽  
Author(s):  
Břetislav Princ ◽  
Otto Exner
Keyword(s):  
Alkaline Medium ◽  
Benzyl Chloride ◽  
Phenyl Group ◽  
H Nmr ◽  
Condensation Products ◽  
Alkylation Reactions

The structure of some compounds reported in the literature as nitrones II has been reexamined using mainly the 1H NMR and mass spectroscopies. The nitrone structure has been confirmed for the condensation products of N-alkylhydroxylamines with aldehydes (IIf) or ketones (IIj,l,m), as well as for the products of alkylation of aldoximes with benzyl chloride (IId,h). Other similar alkylation reactions yield generally a mixture of the nitrone and the dimeric oxazolidine derivative (Va,b,e), in addition to the O-alkylated oxime (VI). The nitrone is assumed to be the primary product in any case, its subsequent dimerization is promoted either by the alkaline medium or by the presence of a phenyl group as in Vg,k.

Alkylation reactions of 5-nitrofurfuryl derivatives as C-acids

1979 ◽  
Vol 44 (8) ◽  
pp. 2511-2516 ◽  
Author(s):  
Josef Prousek ◽  
Adolf Jurášek ◽  
Jaroslav Kováč
Keyword(s):  
Alkaline Medium ◽  
H Nmr ◽  
Phenyl Sulfone ◽  
Alkylation Reactions

5-Nitrofurfuryl bromide (I) and 4-nitrobenzyl bromide (VI) were investigated as possible alkylation reagents in reaction with 5-nitrofurfuryl trichloromethyl sulfone (IV) and 5-nitrofurfuryl phenyl sulfone (V). 1,2-Bis(5-nitro-2-furyl)ethylene (III) was formed from I in an alkaline medium and 1,2-bis(5-nitro-2-furyl)ethane (X) in the presence of furfuryl mercaptan. Products of this reaction were identified by IR, UV, 1H NMR and mass spectrometries.

New Condensation Products of Rubber Hydrocarbons by the Aid of Benzyl Chloride

1932 ◽  
Vol 5 (2) ◽  
pp. 110-116
Author(s):  
F. Kirchhof
Keyword(s):  
Aluminum Chloride ◽  
Benzyl Chloride ◽  
Condensation Product ◽  
Chemical Properties ◽  
Metal Chlorides ◽  
Condensation Products ◽  
New Type ◽  
The One ◽  
Physical And Chemical ◽  
And Chemical Properties

Abstract The application of the long-known Friedel-Crafts reaction to rubber hydrocarbons led to a new type of condensation products which may be called provisionally aral cyclorubbers (“benzylidene rubbers”), since their benzylidene groups are probably condensed with the polyprene skeleton to cyclic systems. It would not have been foreseen without further work that rubber would form this type of condensation product with aral halides in the presence of aluminum chloride, since on the one hand benzyl chloride is known to form, by the action of aluminum chloride in the Friedel-Crafts reaction, an amorphous, apparently high molecular hydrocarbon of the empirical composition (C7H6)x, and on the other hand rubber in solution is transformed by the metal chlorides, especially aluminum chloride, into amorphous polycyclorubbers. Under definite conditions of condensation with aluminum chloride aral groups are combined with the skeleton of the rubber hydrocarbon with the formation of white to yellowish amorphous bodies which contain, in addition to a small proportion of organically combined chlorine, only carbon and hydrogen, and are therefore to be regarded as hydrocarbons. In their physical and chemical properties these substances resemble the already known amorphous substance of the empirical formula (C7H6)x, which doubtless is polybenzylidene, probably hexabenzylidene.

scholarly journals Synthesis of a Cationic Polyacrylamide under UV Initiation and Its Flocculation in Estrone Removal

2018 ◽  
Vol 2018 ◽  
pp. 1-11 ◽  
Author(s):  
Jiaoxia Sun ◽  
Xiqin Ma ◽  
Xiang Li ◽  
Jianxin Fan ◽  
Qingkong Chen ◽  
...  
Keyword(s):  
Ammonium Chloride ◽  
Removal Rate ◽  
Phenyl Group ◽  
Resonance Spectroscopy ◽  
Scanning Calorimetry ◽  
Floc Size ◽  
Cationic Polyacrylamide ◽  
H Nmr ◽  
Ft Ir ◽  
Dsc Analyses

A ternary cationic polyacrylamide (CPAM) with the hydrophobic characteristic was prepared through ultraviolet- (UV-) initiated polymerization technique for the estrone (E1) environmental estrogen separation and removal. The monomers of acrylamide (AM), acryloyloxyethyl-trimethyl ammonium chloride (DAC), and acryloyloxyethyl dimethylbenzyl ammonium chloride (AODBAC) were used to synthesize the ternary copolymer (PADA). Fourier transform infrared spectroscopy (FT-IR), 1H nuclear magnetic resonance spectroscopy (1H NMR), thermogravimetry/differential scanning calorimetry (TG/DSC), and scanning electron microscopy (SEM) were employed to characterize the structure, thermal decomposition property, and morphology of the polymers, respectively. FT-IR and 1H NMR results indicated the successful formation of the polymers. Besides, with the introduction of hydrophobic groups (phenyl group), an irregular and porous surface morphology and a favorable thermal stability of the PADA were observed by SEM and TG/DSC analyses, respectively. At the optimal condition (pH = 7, flocculant dosage = 4.0 mg/L and E1 concentration = 0.75 mg/L), an excellent E1 flocculation performance (E1 removal rate: 90.1%, floc size: 18.3 μm, and flocculation kinetics: 22.69×10-4 s−1) was acquired by using the efficient flocculant PADA-3 (cationic degree = 40%, and intrinsic viscosity = 6.30 dL·g−1). The zeta potential and floc size analyses were used to analyze the possible flocculation mechanism for the E1 removal. Results indicated that the charge neutralization, adsorption, and birding effects were dominant in the E1 removal progress.

Potential antidepressants: 2-(Phenylthio)aralkylamines

1989 ◽  
Vol 54 (7) ◽  
pp. 1995-2008 ◽  
Author(s):  
Jiří Jílek ◽  
Jiří Urban ◽  
Petr Taufmann ◽  
Jiří Holubek ◽  
Antonín Dlabač ◽  
...  
Keyword(s):  
Nmr Spectra ◽  
Benzyl Chloride ◽  
Lithium Aluminium Hydride ◽  
Pharmacological Profile ◽  
H Nmr ◽  
Lithium Aluminium ◽  
Alternative Approach ◽  
Phenyl Acetonitrile ◽  
Claisen Reaction ◽  
Pharmacological Testing

Reactions of 2-(phenylthio)benzyl chloride with dimethylamine, diethylamine, pyrrolidine, piperidine, morpholine, and 1-methylpiperazine afforded the title compounds VI-XI. Reaction of 2-(phenylthio)benzaldehyde with nitromethane gave the nitrostyrene XIV which was reduced with lithium aluminium hydride to 2-(2-(phenylthio)phenyl)ethylamine (XVI). This was transformed to the N-methyl and N,N-dimethyl derivatives XVIII and XIX. The Claisen reaction of (2-(phenylthio)phenyl)acetonitrile with ethyl acetate afforded compound XXI which was cleaved by phosphoric acid to (2-(phenylthio)phenyl)acetone (XX). The Leuckart-Wallach reaction afforded the formamide XXIII which was used as starting material for preparing the amines XXIV-XXVI. The alternative approach to these compounds starting by reaction of the aldehyde XII with nitroethane was complicated by the fact that in addition to the nitropropene XV 2-(phenylthio)benzonitrile was also formed. The synthetic use of the inhomogeneous XV resulted then in mixtures of amines XXIV-XXVI with IV-VI which was followed by means of mass and 1H NMR spectra. The amines XXIV-XXVI were oxidized to the sulfoxides XXVII-XXIX. The oily bases were transformed to crystalline salts and spectra of all homogeneous bases were recorded. Pharmacological testing showed the amine VI (VÚFB-15 370) to be a promising potential antidepressant. The amines XI and XXV showed also pharmacological profile of potential antidepressants.

Hydrolysis-Condensation of Alkyltin-Trialkoxides

1992 ◽  
Vol 271 ◽  
Author(s):  
François Ribot ◽  
F. Banse ◽  
C. Sanchez
Keyword(s):  
Nmr Spectroscopy ◽  
H Nmr ◽  
Condensation Products

ABSTRACTBuSn(OPri)3 and BuSn(OAmt)3 have been synthesized according to a literature procedure. Their hydrolysis have been studied by 119Sn and 1H NMR spectroscopy. The former precursor yields only a closo-type oxo-hydroxo cation of formula [(BuSn)12O14(OH)6]2+. Investigation of the hydrolysis-condensation products of BuSn(OAmt)3 reveals expanded coordinenceabout the tin atoms from 4 to 5 and 6 when H2O/Sn>l. For butyltin tri-tert-amyloxide, condensation also promotes the formation of a cluster whose structure is as yet unknown.

Preparation and alkylation reactions of 4-nitrobenzyl and 5-nitrofurfuryl sulfones

1988 ◽  
Vol 53 (4) ◽  
pp. 851-856 ◽  
Author(s):  
Josef Prousek
Keyword(s):  
Nmr Spectroscopy ◽  
Dimethyl Sulfoxide ◽  
Mass Spectroscopy ◽  
Substitution Reaction ◽  
Reaction Medium ◽  
Polyethylene Glycols ◽  
H Nmr ◽  
Phenyl Sulfone ◽  
Alkylation Reactions

Substitution reaction of 5-nitrofurfuryl bromide (I) with sodium thiophenoxide and 4-chlorothiophenoxide in dimethyl sulfoxide at 20 °C and oxidation with dimethyl sulfoxide in the reaction medium afforded 5-nitrofurfuryl phenyl sulfone (IVa) and 5-nitrofurfuryl 4-chlorophenyl sulfone (IVb), respectively. Similarly, 4-nitrobenzyl bromide reacted with sodium 4-chlorothiophenoxide to give 4-nitrobenzyl 4-chlorophenyl sulfone (VII) and with sodium phenylsulfinate to afford 4-nitrobenzyl phenyl sulfone (IX). The sulfide intermediates were not isolated. The sulfone IX was used as substrate in alkylation reactions, catalysed by polyethylene glycols. Derivatives IVb and VII were identified by IR and mass spectroscopy, alkylation products by 1H NMR spectroscopy.

Study of keto-enol tautomerism and alkylation reactions of β-ketosulphones of 5-nitrofuran series

1981 ◽  
Vol 46 (12) ◽  
pp. 3115-3121 ◽  
Author(s):  
Adolf Jurášek ◽  
Dana Polakovičová ◽  
Jaroslav Kováč
Keyword(s):  
Methyl Iodide ◽  
Nmr Spectra ◽  
Chemical Investigation ◽  
Ch Acids ◽  
H Nmr ◽  
Methyl Derivatives ◽  
Alkylation Reactions

2-(5-Nitro-2-furyl)-2-oxoethyl 3-X-phenyl sulphones I react with diazomethane in tetrahydrofuran or dioxane to give trisubstituted ethylenes II, i.e. 1-(5-nitro-2-furyl)-1-methoxy-2-(4-X-phenylsulphonyl)ethylenes (X = H, CH3, OCH3, N(CH3)2, Cl, NO2) which have Z configuration. From results of spectral and chemical investigation it follows that β-ketosulphones of 5-nitrofuran series only exist in ketoform and are very strong CH-acids (pKa 7.82-5.23). Alkylation of the sulphones I (X = H, CH3) with methyl iodide under conditions of extraction alkylation gives the corresponding C-methyl derivatives III. Interpretation is given of IR, UV, 13C and 1H NMR spectra of the sulphones I and II.

Quantitative relations between chemical structure and hepatotoxicity of thiobenzamides

1988 ◽  
Vol 53 (11) ◽  
pp. 2957-2961 ◽  
Author(s):  
Karel Waisser ◽  
Miloš Macháček ◽  
Jean Lebvoua ◽  
Jiří Hrbata ◽  
Jaroslav Dršata
Keyword(s):  
Chemical Structure ◽  
Chemical Shifts ◽  
Phenyl Group ◽  
Total Effect ◽  
Nmr Chemical Shifts ◽  
H Nmr ◽  
Hammett Constants ◽  
Thioamide Group

1H NMR chemical shifts of thioamide protons have been determined for a group of thiobenzamides, and the values obtained have been correlated with the Hammett constants. From the relations found the σm and σp values of thioamide group and some other σ constants describing the total effect of two substituents in the phenyl group have been calculated. The relation between the hepatotoxicity for rats (expressed as log ALT) and the Hammett constants is described by equation of parabola.

Remarks on the barrier to rotation about the Csp2—O bond in anisole

1989 ◽  
Vol 67 (7) ◽  
pp. 1148-1152 ◽  
Author(s):  
Ted Schaefer ◽  
Rudy Sebastian
Keyword(s):  
Molecular Orbital ◽  
Heavy Atom ◽  
Phenyl Group ◽  
Solvent Mixture ◽  
Spin Coupling ◽  
Basis Set ◽  
Coupling Constant ◽  
H Nmr ◽  
Internal Barrier ◽  
Spin Spin Coupling

Molecular orbital computations with the basis set 6-31G are reported for seven values of θ, the torsion angle about the [Formula: see text] bond in anisole. All bond angles and lengths are optimized but the atoms of the phenyl group are constrained to a plane. The relative energies are fit by V(θ)/kJ mol−1 = 7.78(5) sin2θ + 2.41(5) sin2 2θ − 0.54(5) sin2 3θ, where θ is zero when the heavy-atom skeleton is planar. Computations with the basis set 6-31G*(5D) for three values of θ can be reproduced by V(θ)/kJ mol−1 = 6.07 sin2θ + 2.68 sin2 2θ. These results are compared with experimental gas phase data from the literature. The analysis of the 1H nuclear magnetic resonance spectrum of anisole-α-13C in aCS2/C6D12/TMS solvent mixture yields a value of 6J(1H, 13C), the long-range spin-spin coupling constant between the 13C nucleus in the methyl group and thepara proton. Because this coupling constant is proportional to sin2 θ, it is shown, together with previous dynamic nmr measurements, that the barrier to rotation about the [Formula: see text] bond in solution cannot be purely twofold. The internal potential must also contain a fourfold term of the same sign as that of the twofold component. If the V2/V4 ratio given by the various molecular orbital computations holds in solution, then V2 is 15.0 ± 2.0 kJ/mol and V4 is 5.6 ± 2.2 kj/mol. The apparent doubling of the internal barrier in solution is perhaps unprecedented for such a simple molecule. Keywords: anisole, internal barrier in solution, anisole-α-13C, 1H NMR, conformational behaviour, MO computations.

1D and 2D NMR investigations of the micelle-formation process in 8-phenyloctanoate micelles

2007 ◽  
Vol 85 (3) ◽  
pp. 202-207 ◽  
Author(s):  
Josette M Landry ◽  
D Gerrard Marangoni ◽  
Michael D Lumsden ◽  
Robert Berno
Keyword(s):  
Chemical Shift ◽  
Phenyl Group ◽  
Micelle Formation ◽  
Aromatic Proton ◽  
2D Nmr ◽  
H Nmr ◽  
2D Noesy ◽  
Before And After ◽  
Micellization Process ◽  
Nuclear Overhauser

The micellization process of sodium 8-phenyloctanoate in a deuterated aqueous solution was studied, using 1H NMR spectroscopy and two-dimensional (2D) nuclear Overhauser enhancement spectroscopy (NOESY). 1H NMR spectra, acquired for the sodium 8-phenyloctanoate before and after the critical micelle concentration (CMC) value, showed that large chemical-shift changes were observed for both the aromatic proton peaks and the peaks for the methylene protons near the terminal phenyl group. The plots for the methylene protons near the headgroup do not show these large chemical-shift changes. These observations support the view that the terminal phenyl ring of the surfactant is primarily located in the micellar interior. The 2D NOESY experiments show significant cross-peaks, between the phenyl protons and the methylene protons of the surfactant, that substantiate the conclusions on those drawn from NMR aromatic solute induced shift (ASIS) experiments on the same and similar systems. All these observations are consistent with the Gruen model of the micelle and previous NMR NOESY experiments for other surfactant systems.Key words: surfactants, micelles, NMR, NOESY.

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