Showing papers on "Pyrazoline published in 1985"
TL;DR: In this article, a general reaction scheme was proposed for the synthesis of pyrazole and pyrazoline 1,2-dioxides in moderate yields with lead tetra-acetate.
Abstract: The oxidation of dioximes of aliphatic and cyclic 1,3-diketones with lead tetra-acetate has been investigated. The formation of pyrazole and pyrazoline 1,2-dioxides in moderate yields has been established. A general reaction scheme is proposed.
11 citations
TL;DR: The 3-trimethylsilyl-1-pyrazoline was synthesized by adding diazomethane to vinyl trimethylsilane at room temperature as mentioned in this paper.
7 citations
Journal Article•
TL;DR: In this article, aqueous solution of phenazone, aminophenazone and propyphenazone was used to identify derivatives of pyrazoline, pyrazolidinone, imidazoline, hydantoin, aziridine, phenylhydrazine and aniline.
Abstract: From aqueous solutions of phenazone, aminophenazone, propyphenazone, nifenazone, morazone, noramidopyrine, 4-aminophenazone and isopropylaminophenazone, UV irradiated at lambda = 254 nm in oxygen free atmosphere as well as in the presence of air, 24 decomposition products were isolated and identified as derivatives of pyrazoline, pyrazolidinone, imidazoline, hydantoin, aziridine, phenylhydrazine and aniline.
4 citations
Patent•
19 Apr 1985TL;DR: Tetrafluorobenzofurans of the formula "STR1" are prepared by contacting, at elevated temperature in an aprotic solvent, an ether with a catalytic mixture of metallic cooper and a polydentate or other ligand as discussed by the authors.
Abstract: Tetrafluorobenzofurans of the formula ##STR1## are prepared by contacting, at elevated temperature in an aprotic solvent, an ether of the formula ##STR2## with a catalytic mixture of metallic cooper and a polydentate or other ligand, wherein R 1 is hydrogen, nitro, amino, phthalimido or acetylimido, R 2 is at least one of hydrogen, halo, cyano, alkyl, hydroxy, alkoxy, acyl, acyloxy, alkoxycarbonyl, alkoxycarbonylalkyl, phenyl, phenyloxy, trifluoromethyl or dialkylamino. The products are intermediates in the preparation of pyrazoline insecticides.
3 citations
TL;DR: In this paper, the synthesis of 1α-methyl, 1β-methyl-, and 1α, 2α -methylene-gibberellins required for further investigations into structure-biological activity relationships are described.
Abstract: The syntheses of 1α-methyl-, 1β-methyl-, and 1α,2α-methylene-gibberellins required for further investigations into structure–biological activity relationships are described. Thermolysis of the pyrazoline derived from GA7-3-ketone-7-methyl ester gave, as the major product, the corresponding 1 -methyl enone with minor amounts of the 1α,2α-methyleneGA4-3-ketone-7-methyl ester. The latter compound was reduced and hydrolysed to 1α,2α-methyleneGA4. Reduction of the 1 -methyl enone with sodium borohydride gave 1α-methylGA4methyl ester, which was hydrolysed to 1α-methylGA4, and 1α-methyl-3-epi-GA4, methyl ester which was deoxygenated to give 1α-methylG9. The palladium-catalysed reduction of the 1-methyl enone gave 1β-methylGA4-3-ketone and 1α-methylGA4-3-ketone which were converted into the corresponding 1β-methylGA4 and 1α-methylGA4. The analogous synthesis of the C-l alkylated 13-hydroxylated gibberellins was improved by the use of a phenacyl ester to protect C-7, thus providing routes to 1β-methylGA1, 1α-methylGA1, and 1α,2α-methyleneGA1.Incubation of 1α-methylGA4 with the fungus Gibberella fujikuroi, mutant B1 -41a, gave 1α-methyl-GA1, as the sole metabolite. Incubation of 1β-methylGA4 with the mutant B1 -41 a gave 1 -methylGA3, 1-methylGA7, and 1β-methylGA1 confirming that it is the 1α-hydrogen which is lost in the 1,2-didehydrogenation process in the fungus.
3 citations
2 citations
TL;DR: The crystal and molecular structure of the title compound, derived by lead tetraacetate oxidation of the bis-p-methoxybenzoylhydrazone of 3,3-dimethylpentane-2,4-dione, was studied by an X-ray crystallographic analysis as discussed by the authors.
1 citations
1 citations
TL;DR: In this article, the Oxidation des Pyrazolin-carbonsaureesters (I) with Bleitetraacetat entstehen Gemische der Verbindungen (II)-(XI), deren Zusammensetzung von der Temperatur abhangig ist.
Abstract: Bei der Oxidation des Pyrazolin-carbonsaureesters (I) mit Bleitetraacetat entstehen Gemische der Verbindungen (II)-(XI), deren Zusammensetzung von der Temperatur abhangig ist.
1 citations
TL;DR: In this article, the reactions of 1-pyrazoline-3-spiro-4′-(1′,3′-dioxolan-5′-one) were studied; this compound is the product of the 1,3-dipolar addition of diazomethane to 5-methylene-1,3dioxolane-4-one.
Abstract: The reactions of 1-pyrazoline-3-spiro-4′-(1′,3′-dioxolan-5′-one) were studied; this compound is the product of the 1,3-dipolar addition of diazomethane to 5-methylene-1,3-dioxolan-4-one. Depending on the conditions, thermolysis of the spiro compounds proceeds either with destruction of the pyrazoline ring, or with cleavage of the dioxolane ring, followed by rearrangement to give 1(2)-hydroxymethyl-3(5)-pyrazolecarboxylic acid.
TL;DR: In this article, 3-methyl-9-phenylethynyl-2-azafluoren-9ol and spiro compounds with 2-azaffluorene, indan, pyrazoline, and cyclopropane fragments were obtained starting from 3methyl-2.0-azafenone by successive transformations, and the spatial structures of the synthesized compounds were obtained.
Abstract: 3-Methyl-9-phenylethynyl-2-azafluoren-9-ol, 3-methyl-9-phenacylidene-2-azafluorene, and spiro compounds with 2-azafluorene, indan, pyrazoline, and cyclopropane fragments were obtained starting from 3-methyl-2-azafluorenone by successive transformations. Information regarding the spatial structures of the synthesized compounds was obtained.
TL;DR: The photolysis of 1-azido-2-dialkylaminomethyl-9,10-anthraquinones leads to 2,2 -dialkyl-6H,11H,6,11-dioxanthra[1, 2-d]pyrazoline-1,2-amide(I)imides as mentioned in this paper.
Abstract: The photolysis of 1-azido-2-dialkylaminomethyl-9,10-anthraquinones leads to 2,2-dialkyl-6H,11H,6,11-dioxanthra[1,2-d]pyrazoline-1,2-amide(I)imides. The same products are formed in the thermolysis of the initial compounds; however, they decompose under the reaction conditions.
TL;DR: The kinetics of the complex-formation of the palladium ion with 1,8-dihydroxy-2-(2-pyrazolin-5-azo)naphthalene-3,6-disulfonic acid has been studied in aqueous solution as discussed by the authors.
Abstract: The kinetics of the complex-formation of the palladium ion with 1,8-dihydroxy-2-(2-pyrazolin-5-azo)naphthalene-3,6-disulfonic acid has been studied in aqueous solution (pH 0–5). It has been shown that the rate of the reaction is a maximum at pH 2.8 and falls at pH > 2.9 because of the hydrolysis of the palladium ions and at pH < 2.9 as a consequence of the protonation of the reagent molecule.