scispace - formally typeset
Search or ask a question

Showing papers on "Hydrazone published in 1971"


Journal ArticleDOI
TL;DR: In this paper, it was shown that the hydrazone derived from 8 lost nitrogen to give carbene 14 which in turn produced carbene 11 and 12, and it was further postulated that this loss was compensated by a loss of nitrogen in the resulting carbene.
Abstract: Oxidation of 2-hydrazono-N,N,N′,N′ tetramethylthiooxamide (8) by various reagents did not provide the expected thiadiazole 4, but rather gave azines 11 and 12. It is postulated that the hydrazone derived from 8 lost nitrogen to give carbene 14 which in turn produced 11 and 12.

34 citations


Journal ArticleDOI
TL;DR: The coordination of the cupric ion to nitrogenous ligands differs in the three compounds: cupric protoporphyrin IX dimethyl ester, cupric benzoyl hydrazone, and cupric ortho-vanillin ethylene diamine.
Abstract: The coordination of the cupric ion to nitrogenous ligands differs in the three compounds: cupric protoporphyrin IX dimethyl ester, cupric benzoyl hydrazone, and cupric ortho-vanillin ethylene diamine. Electron paramagnetic resonance studies have been carried out to yield the spin-hamiltonian and bonding parameters of the cupric ion in these compounds. These parameters are compared with those from related compounds.

23 citations


Journal ArticleDOI
TL;DR: The principle of the ring-forming α-aminoalkylation of olefines is applied to the synthesis of a five membered heterocycle in this paper.

20 citations



Journal ArticleDOI
TL;DR: In this paper, the rates of bromination of a series of 5-(arylmethylenehydrazino)tetrazoles, benzylated in the heteroaromatic ring, are independent of the bromine concentration.
Abstract: The rates of bromination (in 70% acetic acid at 25°) of a series of 5-(arylmethylenehydrazino)tetrazoles, benzylated in the heteroaromatic ring, are independent of the bromine concentration. The slow step is a syn–anti-isomerisation of the hydrazone. A mechanism involving rotation about the CN bond is favoured in the light of data on the effect of substituents on the rate of isomerisation. The products formed on bromination are hydrazonyl bromides and the replacement of the labile bromine by external and internal nucleophiles is reported.

16 citations


Patent
24 Aug 1971
TL;DR: In this paper, a yellow dye is obtained by condensing 1-(cyano-carbonamido)-3-imino-isoindolene with 3-acetyl-2:4-dihydroxy-quinoline hydrazone.
Abstract: Dyes are of formula (I): (where X is the residue of a methylene-active cpd. an aromatic or heterocyclic primary amine, R1 is H or 1-4C alkyl, R2 is 1-4C alkyl, phenyl opt. substd. by Cl, Br, OH, CH3 and/or CH3O, indoyl-2, 2-phenyl indolyl-3- or 2,4-dihydroxyquinolyl-3-gp. or R1 and R2 together with the methylene C atom form a 6-membered carbocycle or a 5- or 6-membered heterocycle opt. joined to a benzene nucleus). Prepared e.g. by condensing a cpd. (I) where the -N=CR1R2 gp. is replaced by H, with a hydrazone H2N-N=CR1R2. e.g. a yellow dye is obtained by condensing 1-(cyano-carbonamido)-3-imino-isoindolene with 3-acetyl-2:4-dihydroxy-quinoline hydrazone.

14 citations


Journal ArticleDOI
TL;DR: In this paper, a method for converting substituted benzothiazolylhydrazones of some aromatic aldehydes with lead tetra-acetate to cyclised triazolobenzothiazoles has been developed.
Abstract: In the reaction of benzothiazolylhydrazones of some aromatic aldehydes with lead tetra-acetate the presence of a sulphur atom in the potential cyclisation site of the heteroaryl moiety inhibits the cyclisation reaction. Thus, the reaction of substituted benzothiazolylhydrazones involves an acetoxylation of the hydrazone and not a cyclisation reaction as had previously been reported. Cyclisation of the hydrazone to a triazolobenzothiazole moiety does, however, occur as a minor competitive process. A convenient route for converting the acetoxylated products to cyclised triazolobenzothiazoles has been developed thereby overcoming the most serious limitation in the use of the lead tetra-acetate–hydrazone reaction in the benzothiazole series.

11 citations


Patent
20 Sep 1971
TL;DR: Acyl hydrazone derivatives of 2,2,6,6-tetramethylpiperidine-4-one are stabilizers of organic materials as mentioned in this paper, and they are prepared by reacting a corresponding acid hydrazide with triacetonamine.
Abstract: Acyl hydrazone derivatives of 2,2,6,6-tetramethylpiperidine-4-one are stabilizers of organic materials. They are prepared by reacting a corresponding acid hydrazide with triacetonamine.

11 citations


Patent
M Shea1
06 Jul 1971

11 citations


Patent
10 Sep 1971
TL;DR: In this paper, the authors describe a class of reactive poymers, which are low-molecular-weight materials having the ability to react with POLYFUNCTIONAL COMPOUNDS SUCH as DIISOCYANates OR EPOXY RESINS to form cross-linked structures.
Abstract: TERMINALLY REACTIVE POLYMERS ARE PRODUCED BY OZONIZING HIGH MOLECULAR WEIGHT POLYMERS OF BRANCHED CONJUGATED DIOLEFINS SUCH AS ISOPRENE AND REACTING THE OZONIZED PRODUCTS WITH MODIFYING COMPOUNDS SUCH AS HYDRAZINE, HYDROXYLAMINE AND DIHYDRAZINO COMPOUNDS. THE REACTIVE POLYMERS ARE LOW MOLECULAR WEIGHT MATERIALS HAVING TERMINAL HYDRAZONE, OXIME AND HYDRAZOLE GROUPS; THEY REACT WITH POLYFUNCTIONAL COMPOUNDS SUCH AS DIISOCYANATES OR EPOXY RESINS TO FORM CROSS-LINKED STRUCTURES.

10 citations



Patent
01 Jun 1971
TL;DR: In this article, the authors describe processes for preparing azo compounds by adding hydrocyanic acid to a preformed hydrazone, and oxidizing the hydrazo compound formed by the reaction of a t-aliphatic hydrazine with hydrogen or alkali metal cyanide in water.
Abstract: Unsymmetrical azo compounds: ##EQU1## where (R")3 C-- is tertiary-aliphatic and Z is cyano or a derivative thereof, e.g., 2-t-butylazo-2-cyanopropane; processes for preparing such azo compounds by (a) adding hydrocyanic acid to a preformed hydrazone, ##EQU2## of a ketone to form a hydrazo compound, and oxidizing the hydrazo compound; or (b) oxidizing the hydrazo compound formed by the reaction of a t-aliphatic hydrazine with hydrogen or alkali metal cyanide in water.

Journal ArticleDOI
TL;DR: In this article, the substituents effects on the azo-hydrazone tautomerism of 4-arylazo-2,6-di-t-butylphenols in carbon tetrachloride were studied by means of infrared and visible spectra.
Abstract: The substituents effects on the azo-hydrazone tautomerism of 4-arylazo-2,6-di-t-butylphenols in carbon tetrachloride were studied by means of infrared and visible spectra. The substituents effects on their absorption spectra were discussed. The azo tautomers are predominant in the tautomeric equilibria of 3′- and 4′-substituted derivatives. Considerable participations of the hydrazone tautomers are found in the equilibria of the 2′-substituted derivatives having substituents capable of forming intramolecular hydrogen bonding with hydrazone-hydrogen atom. In the equilibria of 2′,6′-disubstituted derivatives, the positions of the equilibria move some what to the azo side from those of the corresponding 2′-substituted derivatives.

Patent
03 Sep 1971
TL;DR: A COMPOUND SELECTED from the group consisting of 2,6-DICHLOROBENZalDEHYDE (4-(2,6)-DicHLORobenZylIDENEAMINO)-5-METHYL-4H-1,2,4-TRIAZOL-3-TL)HYDRAZONE, N-(2.6)-IMIDE, AND 4-(2.,6-DMDE, and 4.5-BIS-(2
Abstract: 1. A COMPOUND SELECTED FROM THE GROUP CONSISTING OF 2,6-DICHLOROBENZALDEHYDE (4-(2,6-DICHLOROBENZYLIDENEAMINO)-5-METHYL-4H-1,2,4-TRIAZOL-3-TL)HYDRAZONE, 2,6-DICHLOROBENZALDEHYDE (4-HYDROXY-6-METHYL-2-PYRIMIDINYL)HYDRAZONE, N-(2,6-DICHLOROBENZYLIDENEAMINO)-3,5-BIS-(2,6IMIDE, AND 4-(2,6-DICHLOROBENZYLIDENEAMINO)-,5-BIS-(2,6DICHLOROBENZYLIDENEHYDRAZINO)-4H-1,2,4-TRIAZOLE.

Patent
27 Sep 1971
TL;DR: The ERYTHROMYCin AZINE DERIVATIVES are used in the TREATMENT of BACTERIAL, AMOEBIC and TRICHOMONAL INFECTIONS in MAMMALS and BIRDS as discussed by the authors.
Abstract: ERYTHROMYCIN AZINE DERIVATIVES ARE USEFUL IN THE TREATMENT OF BACTERIAL, AMOEBIC AND TRICHOMONAL INFECTIONS IN MAMMALS AND BIRDS, AND ARE PREPARED BY REACTING ERYTHROMYCIN HYDRAZONE OR ERYTHROMYCIN B HYDRAZONE WITH AN APPROPRIATE KETONE OR ALDEHYDE.

Journal ArticleDOI
TL;DR: In this paper, a simple procedure suitable for the g.1.c. separation of many asymmetric acyclic, monocyclic and steroidal ketones was described, which depends on the formation of diastereoisomeric hydrazones separable by g. 1.c., but their attempts to apply such acetalization to the optical resolution of other cyclic ketones were unsuccessful.
Abstract: [Manuscript received November 5, 19501. The diastereoisomeric acetals derived &om (&)-camphor and (-)-butane2,3-diol have been completely separated by gas-liquid chromatography,l but our attempts to apply such acetalization to the optical resolution of other cyclic ketones were unsuccessful. We now describe a simple procedure suitable for the g.1.c. separation of many asymmetric acyclic, monocyclic, and steroidal ketones. The method depends on the formation of diastereoisomeric hydrazones separable by g.1.c. The reagent 2,2,2-trifluoroethyl-1-phenylhydrazine is readily prepared from the commerically available 2,2,2-trifluoroacetophenone and the (+) enantiomer can be obtained optically pure by fractional crystallization of the diastereoisomeric hydrazones derived from 5cc-androstan-17-one, followed by acid hydrolysis. To establish the utility of the gas chromatographic method for the determination of optical purity of asymmetric ketones, it is essential to show that the steric purity of the ketone is retained during hydrazone formation. Since monocyclic ketones, such as (I), (2), (3), (7), and (9) (Table 1) are difficult to prepare and to maintain in an optically pure form, this check was done by condensing 2,6,6-trideutero-2-methylcyclohexanone (2) with the reagent. By a mass spectrometric examination of the resulting hydrazone, it was shown that approximately 30% of the deuterium label had been lost during the condensation reaction. One must conclude that some racemization of the ketone by either enolization or carbanion formation had occurred under our reaction conditions. However, sterically pure hydrazones were obtained from the optically pure ketones (5), (ll), (20), and (21), which are sterically more hindered, and from all ketones which have an asymmetric tertiary cc carbon atom

Journal ArticleDOI
TL;DR: In this article, the E-isomer of the hydrazone can be stabilised in the compounds Mo(CO)4L2, Mo( CO)3L2(PPh3) and Mo(Co)2L2I2.
Abstract: Compounds of the types M(CO)4L2 and Mo(CO)3L2Y have been prepared where M = Cr, Mo, and W, L2=Z-pyridine-2-aldehyde 2′-pyridylhydrazone and Y = PPh3, AsPh3, SbPh3, Ph3PSe and SO2. The E-isomer of the hydrazone can be stabilised in the compounds Mo(CO)4L2, Mo(CO)3L2(PPh3) and Mo(CO)2L2I2. Some results of the halogen oxidations of Mo(CO)4L2 where L2= either E- or Z-hydrazone are presented, compounds such as Mo(CO)3(L2)X2, where L2=Z-hydrazone and X = Br, I, and [L2H2]MoOX5, where X = Cl, Br, having been isolated.

Journal ArticleDOI
TL;DR: The reaction of cyclic amidrazones 1a-g with pyruvic ester, pyruvic acid or benzoylformic acid at room temperature leads to the corresponding hydrazones 3 as mentioned in this paper.
Abstract: Aus cyclischen Amidrazonen 1a–g werden bei Raumtemperatur mit Brenztraubensaureester, Brenztraubensaure oder Benzoylameisensaure die entsprechenden Hydrazone 3 bereitet die z. T. in siedendem Xylol oder Dichlorbenzol einer Cyclokondensation zu den entsprechen den as-Triazino-Derivaten (8–11) unterliegen. Anhand der Spektren wird versucht, fur die isomeren Hydrazone Strukturzuordnungen zu treffen. Syntheses of Condensed Triazines, I Reactions of Cyclic Amidrazones with α-Ketoacid Derivatives The reaction of cyclic amidrazones 1a–g with pyruvic ester, pyruvic acid or benzoylformic acid at room temperature leads to the corresponding hydrazones 3. Some of them undergo cyclocondensation in boiling xylene or dichlorobenzene to give the corresponding as-triazino derivatives (8–11). Attempts are made to assign structures to the isomeric hydrazones with the help of spectral data.

Journal ArticleDOI
TL;DR: In this article, a mechanism for pyrazoline formation involves elimination from the Mannich base to form a vinyl ketone, which then forms a hydrazone (of the right configuration).
Abstract: Aminoguanidinium nitrate reacts with Mannich bases, ArCO·CH2·CH2·NMe2 to form, depending upon the pH, di-β-keto-hydrazines, 1-amidino-Δ2-pyrazolines, or amidinohydrazone dinitrates. These substituted hydrazones do not display hydrazine anchimerism to form pyrazolines, probably because they exist in the wrong geometric form. The suggested mechanism for pyrazoline formation involves elimination from the Mannich base to form a vinyl ketone, which then forms a hydrazone (of the right configuration); subsequently this cyclises to the pyrazoline.

Journal ArticleDOI
TL;DR: In this paper, aryl hydrazonates yields NN-diarylhydrazides, a Chapman-like rearrangement in the hydrazone series.
Abstract: Thermal rearrangement of aryl hydrazonates yields NN-diarylhydrazides, a Chapman-like rearrangement in the hydrazone series.

Journal ArticleDOI
TL;DR: In this article, the bromination of an NN-disubstituted N′-arylmethylenehydrazines (in 70% acetic acid at 20°) exhibits zero-order kinetics, the rate-determining step being a syn-anti isomerisation of the hydrazone.
Abstract: The bromination of an NN-disubstituted N′-arylmethylenehydrazines (in 70% acetic acid at 20°) exhibits zero-order kinetics, the rate-determining step being a syn–anti isomerisation of the hydrazone. The kinetics of bromination are independent both of the concentration and of the nature (Br2 or Br3–) of the brominating species. Substituents (m- and p-) in the aryl ring have a small electronic effect on the rate of isomerisation (ρ– 0·29), while large substituents ortho in this ring retard the rate (δ 0·145). The electron-withdrawing acetyl and benzoyl groups as substituents on the amino-nitrogen atom cause eleven- and twenty-eight-fold increases in rate (relative to the methyl-substituted hydrazone). Contrary to earlier observations, methine bromination does occur and several novel hydrazonyl bromides have been isolated and characterised by conversion into hydrazides.

Journal ArticleDOI
TL;DR: The benzonorbornadienone hydrazone (VI) as mentioned in this paper has been prepared and an explanation given for its high thermal stability compared with the parent ketone (III).
Abstract: The benzonorbornadienone hydrazone (VI) has been prepared and an explanation given for its high thermal stability compared with the parent ketone (III).


Patent
02 Aug 1971
TL;DR: A COMBINATION of an ALLOXYALDEHYDE HYDRAZONE and GLYCIDOL is used to stabilize CHLORINATED ALIPHATIC HYDRO CARBON SOLVENTS as discussed by the authors.
Abstract: A COMBINATION OF AN ALLOXYALDEHYDE HYDRAZONE AND GLYCIDOL IS USED TO STABILIZE CHLORINATED ALIPHATIC HYDRO CARBON SOLVENTS.

Journal ArticleDOI
TL;DR: In this article, the reaction of 2-phenylimino- and 2-(p-tolylimino)thiazolidin-4-ones with benzene-, p-nitrobenzene, p-sulfamoylbenzenes, and p-toluenediazonium chlorides in glacial acetic acid in the presence of anhydrous sodium acetate (pH of the medium 4.5-5.0) has been studied.
Abstract: The reaction of 2-phenylimino- and 2-(p-tolylimino)thiazolidin-4-ones with benzene-, p-nitrobenzene, p-sulfamoylbenzene-, and p-toluenediazonium chlorides in glacial acetic acid in the presence of anhydrous sodium acetate (pH of the medium 4.5–5.0) has been studied. A spectroscopic investigation in the IR and UV regions has shown that the 5-(p-nitrophenylazo) derivatives of thiazolidin-4-one exist in the azo tautomeric form; the 5-phenylazo and p-tolylazo derivatives of thiazolidin-4-one are mixtures of the azo and hydrazone tautomers.