Hydroxylamine Hydrochloride (hydroxylamine + hydrochloride)

Distribution by Scientific Domains


Selected Abstracts


ChemInform Abstract: Selective and Efficient Oxidation of Aldehydes to Their Corresponding Carboxylic Acids Using H2O2/HCl in the Presence of Hydroxylamine Hydrochloride.

CHEMINFORM, Issue 41 2008
Kiumars Bahrami
Abstract ChemInform is a weekly Abstracting Service, delivering concise information at a glance that was extracted from about 200 leading journals. To access a ChemInform Abstract of an article which was published elsewhere, please select a "Full Text" option. The original article is trackable via the "References" option. [source]


Selective and Efficient Oxidation of Aldehydes to Their Corresponding Carboxylic Acids Using H2O2/HCl in the Presence of Hydroxylamine Hydrochloride

CHINESE JOURNAL OF CHEMISTRY, Issue 6 2008
Kiumars BAHRAMI
Abstract A wide variety of aldehydes were efficiently converted to their corresponding carboxylic acids in high yields using H2O2/HCl in the presence of hydroxylamine hydrochloride. In addition, selective oxidation of aldehydes in the presence of other functional groups such as hydroxyl group, carbon-carbon double bond and other heteroatoms can be considered a noteworthy advantage of this method. [source]


Development and validation of fixed-time method for the determination of isoxsuprine hydrochloride in commercial dosages forms

DRUG TESTING AND ANALYSIS, Issue 9 2010
Dr Nafisur Rahman
Abstract The main aim of this work was to develop a kinetic spectrophotometric method for the quantitative analysis of isoxsuprine hydrochloride in commercial tablets. The method is based on the reaction of isoxsuprine hydrochloride (ISx) with hydroxylamine hydrochloride and ammonium cerium (IV) nitrate in sulphuric acid medium at room temperature which resulted in the formation of yellow-coloured product peaking at 380 nm. The reaction is followed spectrophotometrically by measuring the absorbance as a function of time. Fixed time method (,A = A4,A2, where A2 and A4 refer to absorbance measurements taken at 2 and 4 min, respectively) was adopted for constructing the calibration curve which was found to be linear over the concentration range of 30,80 µgmL,1 with molar absorptivity of 5.95 × 103 L mol,1 cm,1. The method has been applied successfully to the determination of isoxsuprine hydrochloride in tablets. Statistical comparison (point and interval hypothesis tests) of the results showed that there is no significant difference between the proposed method and reference method. Copyright © 2010 John Wiley & Sons, Ltd. [source]


Palladium-Catalyzed One-Pot Conversion of Aldehydes to Amides

ADVANCED SYNTHESIS & CATALYSIS (PREVIOUSLY: JOURNAL FUER PRAKTISCHE CHEMIE), Issue 2-3 2010
Md Ashif Ali
Abstract The palladium-catalyzed one-pot conversion of aldehydes into primary amides in the presence of hydroxylamine hydrochloride in aqueous dimethyl sulfoxide (DMSO) at moderate temperature is described. The process is selective and free from the addition of an external chelating ligand. [source]


Synthesis and crystal structure of 3,5-diacetyl-4-methylpyrazole

JOURNAL OF HETEROCYCLIC CHEMISTRY, Issue 5 2010
Moha Outirite
The 3,5-diacetyl-4-methylpyrazole diketone has been synthesized and its crystal structure has been determined. This diketone reacts with hydroxylamine hydrochloride to give the dioxime derivative. This reaction, conducted in presence of copper II ions, leads to the formation of L2M2 copper II complexes. J. Heterocyclic Chem., (2010). [source]


Ethyl-3,4-diaroyl-2-cyanobutyrate: A Synthon for novel heterocycles

JOURNAL OF HETEROCYCLIC CHEMISTRY, Issue 6 2009
Adivireddy Padmaja
A new class of aminopyrazolones, aminoisoxazolones, aminopyrimidinones, and thioxopyrimidinones were synthesized from Michael adduct, ethyl-3,4-diaroyl-2-cyanobutyrate, on reaction with different nucleophiles, hydrazine hydrate, hydroxylamine hydrochloride, and urea derivatives. J. Heterocyclic Chem., (2009). [source]


2-Trifluoroacetyl-1-methoxycycloalkenes: A convenient precursor for the synthesis of geminated polymethylene trifluoromethyl substituted heterocycles

JOURNAL OF HETEROCYCLIC CHEMISTRY, Issue 2 2009
Helio Gauze Bonacorso
This article describes the methodology that allows the simultaneous introduction of a trifluoromethyl group and a 7-, 8-, and 10-membered cycloalkane ring fused to heterocyclic derivatives. A series of 10 geminated polymethylene trifluoromethyl substituted isoxazolines, pyrazoles, pyrimidinones, and a pyrazolyl-quinoline were obtained in moderate to good yields from the reaction of three 2-trifluoroacetyl-1-methoxycycloalkenes derived from cycloheptanone, cyclooctanone, and cyclododecanone with hydroxylamine hydrochloride, hydrazine hydrochloride, urea, and 7-chloro-4-hydrazinoquinoline. J. Heterocyclic Chem., (2009). [source]


,-Oxoanilides in heterocyclic synthesis: An expeditious synthesis of new polyfunctionally substituted pyridine and pyrazole derivatives

JOURNAL OF HETEROCYCLIC CHEMISTRY, Issue 6 2008
A. M. Hussein
3-Oxo- N -{4-[(pyrimidin-2-ylamino)sulfonyl]phenyl}butanamide 3 was condensed with (DMF-DMA) in refluxing dry dioxane to yield branched structure 4 not its linear isomeric 5. Compound 4 readily reacted with active methylene to yield compounds 8a-c, 14, 17 and 20 respectively. Also enaminone 4 reacted with phenyl hydrazine giving 24 and 25. In contrast, when compound 4 reacted with hydrazine hydrate in the same experimental conditions pyrazole derivative 27 was obtained. Furthermore, condensation of anilide 3 with triethylorthoformate in refluxing acetic anhydride afforded the ethoxy methylene derivative 28. On the other hand, compound 28 was reacted with active methylene reagents, and hydrazines to afford the products identical in all respects (mp., mixed mp., and spectral data) with those corresponding to compounds 6-27 respectively. Similarly, compound 3 was reacted with hydrazine hydrate to afford the reaction product 29. Also, compound 3 reacted with cyanoacetamide in refluxing ethanolic pipridine solution to yield the pyridine derivative 30. Finally, 3 reacted with hydroxylamine hydrochloride in refluxing ethanol/sodium acetate solution to yield the acyclic oxime derivative 31. [source]


New one step synthesis of 3,5-disubstituted 1,2,4-oxadiazoles

JOURNAL OF HETEROCYCLIC CHEMISTRY, Issue 6 2007
Moha Outirite
Disubstituted 1,2,4-oxadiazoles have been synthesized in good yields and good purity in one pot procedure by reaction of aromatic nitriles, hydroxylamine hydrochloride and sodium carbonate in ethylene glycol under heating at 195°C. The structures of different 1,2,4-oxadiazoles obtained were confirmed by 1H, 13C NMR and mass spectroscopy. [source]


Studies with enamines: Reactivity of N,N -dimethyl- N -[(E)-2-(4-nitrophenyl)-1-ethenyl]amine towards nitrilimine and aromatic diazonium salts

JOURNAL OF HETEROCYCLIC CHEMISTRY, Issue 3 2007
Hamad M. Al-Matar
In the presence of triethylamine, cycloaddition reaction of enamine 1 with hydrazonoyl halides 2 followed by dimethylamine elimination was achieved, yielding the corresponding 1,3,4-trisubstituted pyrazoles 4. Coupling of enamine 1 with aromatic diazonium salts afforded 2-(arylhydrazono)-2-(4-nitrophenyl)acetaldehyde 9 in good yield. Refluxing the phenyl hydrazone 9a with chloroacetone in ethanol in the presence of triethylamine afforded 1,3,5-trisubstituted pyrazole 12a, formed via intermediate 11a. Reaction of 9a with hydroxylamine hydrochloride in ethanol in the presence of anhydrous sodium acetate yielded oxime 13a which was irradiated in a microwave oven in the presence of acetic acid to afford a mixture of 15a and 16a. [source]


Spiro-heterocycles from substituted pyridines, pyrans and thiopyrans

JOURNAL OF HETEROCYCLIC CHEMISTRY, Issue 6 2004
Venkatapuram Padmavathi
A new class of spiro-pyrimidines, pyrazoles and isoxazoles are prepared by nucleophilic reaction of 3,5-diaroyl-2,6-diaryl-piperidine-4,4-dicarbonitrile (1), 3,5-diaroyl-2,6-diaryl-tetrahydropyran-4,4-dicarbonitrile (2) and 3,5-diaroyl-2,6-diaryl-tetrahydrothiopyran-4,4-dicarbonitrile (3) with urea, N,N'-dimethyl urea, thiourea, hydrazine hydrate and hydroxylamine hydrochloride. [source]


Studies on the reactions of cyclic oxalyl compounds with hydrazines or hydrazones : Synthesis and reactions of 4-benzoyl-1-(3-nitrophenyl)-5-phenyl-1H -pyrazole-3-carboxylic acid

JOURNAL OF HETEROCYCLIC CHEMISTRY, Issue 5 2002
Ahmet, ener
The 1H -pyrazole-3-carboxylic acid 2, obtained from the furan-2,3-dione 1 and N -Benzylidene- N'-(3-nitrophenyl) hydrazine, was converted via reactions of its acid chloride 3 with various alcohols or N-nucleo-philes into the corresponding ester or amide derivatives 4 or 5, respectively. Nitrile 6 and anilino-pyrazole acid 7 derivatives of 2 were also obtained by dehydration of 5a in a mixture of SOCl2 with DMF and reduction of 2 with sodium polysulphide, respectively. While cyclocondensation reactions of 2 or 7 with phenyl hydrazine or hydrazine hydrate and 6 with only anhydrous hydrazine lead to derivatives of pyrazolo[3,4- d]-pyridazinone 8 and pyrazolo[3,4- d]pyridazine amine 9, respectivel. The reaction of 2 with 2-hydrazinopyri-dine provided hydrazono-pyrazole acid derivative 10, which was decarboxylated to give hydrazono-pyra-zole derivative 11. Pyrazolo[4,3- d]oxazinone 12 and 2-quinolyl pyrazolo[3,4- d]pyridazine 13 derivatives were also prepared by cyclocondensation reactions of 2 with hydroxylamine hydrochloride and 7 with acetaldehyde, respectively. [source]


Synthesis of some novel 3,7-dimethyl-4H -pyrazolo[5,1-c][1,2,4]triazin-4-ones

JOURNAL OF HETEROCYCLIC CHEMISTRY, Issue 3 2001
Ahmed A. El-Barbary
Some novel 3,7-dimethyl-6H -pyrazolo[5,1-c][1,2,4]triazin-4-ones were prepared (3a-g). Compounds 3a,b were treated with hydrazines to afford various products 7a,b, 8a,b, 9 and lla,b depending on the type of hydrazine derivative and reaction conditions. The benzoyloxyimino-pyrazolo[5,1-c][1,2,4]triazines (13a,b) were synthesized by refluxing of compounds 3a,b with hydroxylamine hydrochloride to afford the corresponding oxime derivatives followed by treatment with benzoyl chloride. [source]


Surface-enhanced resonance Raman spectroscopy of rifamycins on silver nanoparticles: insight into their adsorption mechanisms

JOURNAL OF RAMAN SPECTROSCOPY, Issue 9 2006
Barry D. Howes
Abstract Three widely used antibiotics from the rifamycin family, rifamycin SV sodium salt, rifampicin and rifaximin, have been characterized by resonance Raman (RR) and surface-enhanced resonance Raman spectroscopy (SERRS). SERRS spectra were recorded using aqueous silver colloidal dispersions prepared with two reducing agents, sodium borohydride and hydroxylamine hydrochloride, for a range of pH values to identify the SERRS-active substrate surface most suitable for each of the three antibiotics. Rifampicin was found to give intense SERRS signals only for the borohydride-reduced colloid and only at pH < 7.7, whereas the hydroxylamine HCl-reduced colloid was the best substrate for rifaximin, giving considerably more intense SERRS spectra than the borohydride colloid. SERRS spectra of rifaximin were observed only at pH < 7.0. It is proposed that the marked pH dependence of the SERRS enhancement results from a transition from an anionic to a neutral zwitterionic state. SERRS spectra of rifamycin SV were not observed for any experimental conditions. The antibiotics display remarkably contrasting SERRS behaviour, reflecting differences in the nature of the substituent groups on the chromophore ring. A vibrational assignment of the RR spectra and detailed comparison between the RR and SERRS data have given insight into the mechanism of adsorption of the antibiotics onto the Ag surface. Rifampicin and rifaximin adsorb adopting an approximately similar vertical orientation of the chromophore ring with respect to the surface; however, rifampicin adsorbs by direct chemical interaction with the Ag whereas rifaximin does not form a direct bond with the Ag surface. Copyright © 2006 John Wiley & Sons, Ltd. [source]


Surface-enhanced Raman scattering study of the adsorption of the anthraquinone pigment alizarin on Ag nanoparticles

JOURNAL OF RAMAN SPECTROSCOPY, Issue 11 2004
M. V. Cańamares
Abstract FT-Raman and surface-enhanced Raman scattering (SERS) spectroscopy were applied in the vibrational characterization and study of the adsorption and acidity behavior of the highly fluorescent anthraquinone dye alizarin on Ag colloids prepared by chemical reduction with hydroxylamine hydrochloride. The SERS spectra were obtained at different conditions of pH, excitation wavelength and pigment concentration in order to deduce the adsorption mechanism of this molecule. On the basis of the results found we propose an adsorption model for alizarin, which has a different acidic behavior on the metal surface to that in solution. On the metal the deprotonation order of the OH groups changes with respect to the aqueous solution, the OH in position 1 being the first to be ionized instead of that in position 2 as occurs in solution. The two main alizarin forms identified on the metal surface correspond to the mono- and dianionic alizarin species. Copyright © 2004 John Wiley & Sons, Ltd. [source]


Detection of carbonyl groups in triterpenoids by hydroxylamine hydrochloride derivatization using electrospray ionization mass spectrometry

RAPID COMMUNICATIONS IN MASS SPECTROMETRY, Issue 12 2008
Xin Liu
A rapid, simple electrospray ionization mass spectrometry (ESI-MS) sensitivity enhancement method for detecting carbonyl groups in triterpenoids has been developed by using hydroxylamine hydrochloride (NH2OH,·,HCl) as a derivatization reagent. We use the oxime formed during the derivatization reactions and its Beckmann rearrangement intermediates as a means of detecting the carbonyl groups originally present in these triterpenoids. In comparison with other derivatization methods reported in the literature, this method is simple, specific and can be used to detect carbonyl groups in triterpenoids which have low polarity and are poorly or non-ionizable. Moreover, it can also be used to detect hydroxyl groups by using the Dess-Martin periodinane (DMP) to convert primary and secondary hydroxyls into carbonyl groups. Copyright © 2008 John Wiley & Sons, Ltd. [source]


Selective and Efficient Oxidation of Aldehydes to Their Corresponding Carboxylic Acids Using H2O2/HCl in the Presence of Hydroxylamine Hydrochloride

CHINESE JOURNAL OF CHEMISTRY, Issue 6 2008
Kiumars BAHRAMI
Abstract A wide variety of aldehydes were efficiently converted to their corresponding carboxylic acids in high yields using H2O2/HCl in the presence of hydroxylamine hydrochloride. In addition, selective oxidation of aldehydes in the presence of other functional groups such as hydroxyl group, carbon-carbon double bond and other heteroatoms can be considered a noteworthy advantage of this method. [source]


Synthesis of Antipyrine Derivatives Derived from Dimedone

CHINESE JOURNAL OF CHEMISTRY, Issue 4 2007
E. S. H. Ei ashry
Abstract Coupling of dimedone with the diazonium salt of 4-aminoantipyrine afforded 2,3-dimethyl-4-[2-(5,5-dimethyl- 2,6-dioxocyclohex-2-ylidend)-hydrazino]-5-oxo-1-phenylpyrazoline (3). Reaction of 3 with excess phenylhydrazine gave the mixed trishydrazone derivative 4. Treatment of 3 with hydroxylamine produced the bisoxime 5 which upon dehydrative cyclization with acetic anhydride gave the corrsponding tetrahydrobenzo[d][1,2,3]triazole derivative 7. A one-pot synthesis of 7 was done by reacting 3 with hydroxylamine hydrochloride in pyridine, followed by heatment with acetic anhydride. [source]