Showing papers on "Hydrazone published in 1983"

The effect of stereochemistry on 1JC—H at the sp2 carbons of oxime, hydrazone, and imine derivatives of aldehydes

Abstract: A comparison of the magnitudes of 1JC—H at the aldehydic carbon of both the syn and anti isomers of aldehyde derivatives (oximes, hydrazones, and imines) has shown a consistently greater value, by about 20 Hz, for the syn isomer. Regardless of its origin, this stereochemical correlation should prove useful in providing configurational assignments.

Alkylation of a Chiral Hydrazone by Means of Asymmetric Addition of Grignard Reagents to the Carbon-Nitrogen Double Bond

Abstract: A chiral hydrazone, (E)-(S)-N'-benzylidene-N, 3-dimethyl-2-hydrazinobutanol (6), was synthesized from (S)-valinol. Compound 6 was reacted with Grignard reagents to give optically pure (2S, 1'S)-N, 3-dimethyl-N'-1'-phenylalkyl-2-hydrazinobutanols (7a and 7b). However, N'-2'-aryl-1'-phenylethyl-N, 3-dimethyl-2-hydrazinobutanols (7c and 7d) were each obtained as a mixture of two diastereomers. Nitrogen-nitrogen bonds of 7a and 7b were cleaved by hydrogenolysis to give (S)-1-phenylalkylamines (8a and 8b), and their absolute configurations and optical purities were confirmed. These reactions were assumed to proceed via the chelated sixmembered ring intermediates.

Intermolecular proton transfers in the solid state. Conversion of the hydroxyazo into the quinone hydrazone tautomer of 2-amino-3-hydroxy-6-phenylazopyridine. X-Ray crystal structures of the two forms

Abstract: The thermal transformation of the low (1a) to the high temperature (1b) form of 2-amino-3-hydroxy-6-phenylazopyridine has been studied by differential scanning calorimetry and variable temperature i.r. spectroscopy. Form (1a) is converted into (1b) through two intermediate phases and the i.r. spectra show changes in the >CC< and –NN– stretches. X-Ray crystal structures of (1a and b) have been determined. The red crystals of (1a) are orthorhombic, a= 10.026(7), b= 20.452(9), c= 10.111(9)A; the space group is Pbca and the structure has been refined to R 0.080 for 443 non-zero reflections. The blue crystals of (1b) are monoclinic, a= 22.666(6), b= 3.886(4), c= 11.373(7)A, β= 91.82(3)°; the space group is P21/c and the structure has been refined to R 0.048 for 607 non-zero reflections. The bond lengths in (1a and b) are in accord with a hydroxyazo and a quinone hydrazone structure, respectively. The hydrogen bonding in each form can only be explained if (1a) is the azo and (1b) the hydrazone tautomer. In the crystal structure of (1a), the hydroxy-group is close to an azo-group of an adjacent molecule and the solid state tautomerization can be accounted for by an intermolecular co-operative shift of protons across the various hydrogen bonds in structure (1a).

13C and 15N NMR study of azo-hydrazone tautomerism in azo dyes containing amino or acetamido groups

Abstract: Etude a partir de spectres RMN de 13 C et 15 N, de la tautomerie azo-hydrazone, dans des colorants azoiques contenant des groupes NH 2 ou NHCOCH 3 en position ortho ou para sur des squelettes de benzene, naphtalene et anthracene

Electrophotographic photoreceptor with hydrazone derivative

Abstract: An electrophotographic photoreceptor having formed on an electrically conductive support a light-sensitive layer containing a hydrazone derivative of formula (I) as a photoconductive material is disclosed: ##STR1## wherein Z is a divalent hydrocarbon group necessary to form in conjunction with a nitrogen atom a 5- or 6-membered nitrogen-containing heterocyclic ring condensed to the benzene ring; R1 is an aryl group or a heterocyclic group; R2 is a hydrogen atom, an alkyl group or an aryl group; X is a hydrogen atom, a halogen atom, an alkyl group, a substituted amino group, an alkoxy group or a cyano group; and n is an integer of 0 or 1. This hydrazone derivative exhibits great carrier transporting ability when it is incorporated in the light-sensitive layer.

Synthesis of the 1,2,4-Triazolo[4,3-a]quinazolin-5-ones and Related Compounds

Abstract: 2-Hydrazino-3-phenyl-4(3H)-quinazolinone (1) underwent ring closure with aliphatic acid, aldehydes, and carbon disulfide to 1-alkyl-, 1-aryl-, and 1-mercapto-4-phenyl-1,2,4-triazolo[4,3-a]quinazolin-5(4H)-ones (7) for instance. The 1-alkylthio-3-phenyl-1,2,4-triazolo[4,3-a]quinazolin-5(4H)-ones were readily obtained from 7 and alkyl halides. Reaction of 1 with ethyl acetoacetate gave the corresponding hydrazone which was readily converted into 2-(3-methyl-5-oxo-2-pyrazolin-1-yl)-3-phenyl-4(3H)-quinazolinone.

A new, convenient synthesis of selenoketones

Abstract: Dimagnesium salts of hydrazones react with Se2Cl2 in the presence of tri-n-butylamine to give selenoketones in moderate to good yields.

Synthesis of 3-methyleneazetidin-2-one derivatives from α-keto-amides

Abstract: Several α-methyleneazetidin-2-one derivatives (CH2[graphic omitted]HR2, R1= cyclohexyl, PhCH2; R2= H, Me, Et, Prn, etc.) were prepared from the 2-(2,4,6-tri-isopropylbenzenesulphonylhydrazones) of primary α-ketoamides (CH3COCONHR1) using the Shapiro reaction. Thus, trimetallation of these hydrazone derivatives at –78 °C and warming to between –10 and +25° C gave the allenic dianions [CH2CC(O–)N–R]. Reaction of these with the aldehydes (R2CHO), followed by toluene-4-sulphonyl chloride or -sulphonic anhydride, gave the title β-lactams.

New metal-chelate complexes derived from the condensation product of biacetylmonoxime andN,N-dimethylglycine hydrazide hydrochloride (Girard's D Reagent)

Abstract: The reactions between the condensation product of biacetylmonoxime andN,N-dimethylglycine hydrazide hydrochloride, [BMGD]Cl, and the hydrated NiII, CuII, CdII, HgII and UVIO2 salts give chelate complexes of types [M(BMGD)Cl2]Cl (M = CdII or HgII), [Cu(BMGD)2Br2]Cl2 and [M(BMGD-H)2(H2O)2]Cl2 · YH2O (M=NiII, CuII or UVIO2) Elemental analyses, magnetic measurements and spectra (ir, visible, nmr) have been used to characterize the complexes Ir spectral data show that the ligand is monodentate, coordiingvia the azomethine group of the hydrazone, or bidentate, coordinating through the azomethine and the carbonyl oxygen groups The enolization of the carbonyl oxygen involves the NH rather than the CH2 group The stereochemistry of the NiII and CuII complexes is discussed

A kinetic determination of ultratrace amounts of chromium(iii) by its catalytic effect

Abstract: A new sensitive kinetic method is proposed for the determination of chromium(III). The method is based on its catalytic effect on the reaction of 3-methyl-2-benzothiazolone hydrazone with N,N-dimethylaniline to form a violet compound (λmax=590 nm) in the presence of hydrogen peroxide and ethylenediamine-N,N,N′,N′-tetraacetic acid as an activator. The method is selective and sensitive.

3-aryl-7-chloro-3,4-dihydroacridine-1,9(2H,10H)-dione 1-oximes and 1-hydrazone derivatives, their salts, a process for their preparation, agents containing them and their use

Abstract: 3-Aryl-7-chloro-3,4-dihydroacridine-1,9(2H,10H)-dione 1-oximes and 1-hydrazone derivatives of the formula I ##STR1## and their physiologically tolerated acid addition and ammonium salts are described, as is a process for their preparation. The new compounds are chemotherapeutic agents and are active against protozoa, especially malaria plasmodia.

Insecticidal benzoyl hydrazone derivatives

Abstract: Compounds of the formula ##STR1## wherein R 1 , R 2 , R 3 and R 4 are as herein defined useful as insecticides, is described.

Electrophotographic hydrazone plate

Abstract: An electrophotographic plate comprising a photosensitive layer containing a hydrazone compound represented by the general formula: ##STR1## (where X, Y and Z represent independently hydrogen atom, a lower alkyl group, a lower alkoxy group, phenoxy group or an arylalkoxy group; R represents hydrogen atom, a lower alkyl group, allyl group, an aralkyl group or an optionally substituted phenyl group; m and l represent independently 1 or 2; and n represents 0 or 1).

Fischer indolization and its related compounds. XIX. Syntheses of ethyl 4-methoxy- and ethyl 5-methoxy-1-phenyl-3H-benz(e)indole-2-carboxylates.

Abstract: Synthese des composes du titre par synthese de Fischer a partir des α-[methoxy-3- et methoxy-4 naphtyl-2hydrazono] benzenepropionates d'ethyle

New process for the preparation of diphenyl-3,4 methyl-5 pyrazole derivatives

Abstract: Process for the preparation of compounds having the formula:$(10,)$wherein R is a straight or branched alkyl group, having from 1 to 6 atoms of carbon or a phenyl group, characterized in that a hydrazone is reacted within an aprotic polar solvant and at a temperature comprised between 0?oC and the solvant boiling temperature, in presence of a base, said hydrazone having the formula:$(10,)$wherein R has the same meaning as in the formula (I), with an acetyl halide or an acetic acid ester having the formula:$(3,)$wherein X represents a halogen atom or a lower alkoxy group. The compounds of formula (I) are particularly useful for the preparation of drugs.

Synthesis of new 2-pyridylhydrazones and 2-quinolylhydrazones containing 2-thiophene or 2-furan groups

Abstract: Syntheses par action d'hydrazino-2 pyridine ou -quinoleine avec des derives du furfural ou du thiophenecarbaldehyde-2 ou avec l'acetyl-2 thiophene