Heterocyclic synthesis from 3-amino-4-cyanopyrazole

1990 ◽  
Vol 55 (3) ◽  
pp. 728-733 ◽  
Author(s):  
Ali Deeb ◽  
Medhat El-Mobayed ◽  
Abdel Naby Essawy ◽  
Adel Abd El-Hamid ◽  
Atef Mohamid Abd El-Hamid
Keyword(s):  
Acetic Acid ◽  
Zinc Chloride ◽  
Quinoline Derivative ◽  
Phenyl Isothiocyanate ◽  
Heterocyclic Synthesis

3-Amino-4-cyanopyrazole I reacts with hydroxylamine and with hydrazine to yield 1H,6H-3-aminopyrazolo[3,4-c]pyrazole (III and IV). Diazotized IV couples with 2-naphthol to give the arylazo derivative VI which cyclizes to 9H-naphthol[2,1-e]pyrazolo[3',4':3,4]pyrazolo[5,1-c]-[1,2,4]triazine VII by means of acetic acid. The pyrazol-5-ylthiourea obtained from I and phenyl isothiocyanate undergoes base-catalyzed cyclization to give pyrazolo[3,4-d]pyrimidinethione derivative IX. Compound I reacts with cyclohexane in the presence of zinc chloride to give the tetrahydropyrazolo[3,4-b]quinoline derivative XI. The reaction of I with pyridine 1-oxide affords 4H,5H-pyrazolo[5',1':2,3] [1,2,4]triazolo[1,5-a]pyridine-3-carbonitrile XII.

The Meisenheimer rearrangement in heterocyclic synthesis. II. Synthesis and X-ray crystal structure of a tetrahydro-1H-2,3-benzoxazocine and preparation of a hexahydro-2,3-benzoxazonine

1980 ◽  
Vol 33 (6) ◽  
pp. 1323 ◽  
Author(s):  
JB Bremner ◽  
EJ Browne ◽  
PE Davies ◽  
CLWAH Raston
Keyword(s):  
Molecular Structure ◽  
Crystal Structure ◽  
Acetic Acid ◽  
Crystal And Molecular Structure ◽  
Phosphorus Oxychloride ◽  
Crystallographic Analysis ◽  
Heterocyclic Synthesis ◽  
Reaction Conditions ◽  
X Ray ◽  
Heterocyclic Derivatives

The heterocyclic derivatives, 8,9-dimethoxy-3-methyl-1-phenyl-3,4,5,6- tetrahydro-1H-2,3-benzoxazocine(3a) and 9,10-dimethoxy-3-methyl-1- phenyl-1,3,4,5,6,7-hexahydro-2,3-benzoxazonine (3b),examples of two new ring systems, have been prepared by Meisenheimer rearrangement of the corresponding 2-benzazepine and 2-benzazocine N-oxide derivatives (2a) and (2b). The Bischler-Napieralski-type cyclization reaction was used in the preparation of the tertiary amine precursors of these N-oxides reaction conditions for the cyclization were critical and phosphorus oxychloride in refluxing butanenitrile was found to give the best yields of the seven- or eight-membered cyclic imine intermediates. Reductive cleavage of the benzoxazocine derivative (3a) with zinc in acetic acid followed by N-methylation gave the expected product, [2-{3- (dimethylamino)propyl}-4,5-di-methoxyphenyl]phenylmethanol (12). The crystal and molecular structure of (3a) has been determined by X-ray crystallographic analysis.

Enaminones as Building Blocks In Heterocyclic Synthesis: A New One Pot Synthesis of Polyfunctional Substituted Pyridines

2001 ◽  
Vol 56 (10) ◽  
pp. 1074-1078 ◽  
Author(s):  
Samia Michel Agamy ◽  
Mervat Mohammed Abdel-Khalik ◽  
Mona Hassan Mohamed ◽  
Mohammed Hilmy Elnagdi
Keyword(s):  
Acetic Acid ◽  
Double Bond ◽  
Aromatic Aldehyde ◽  
Michael Addition ◽  
Ammonium Acetate ◽  
Building Blocks ◽  
Heterocyclic Synthesis ◽  
One Pot ◽  
Active Methyl ◽  
Substituted Pyridines

Enaminones react with a variety of active methyl and methylene reagents in presence of ammonium acetate to yield functionally substituted pyridines in good yields. The reaction proceeded via initial Michael addition across the double bond followed by cyclization. The reaction of enaminone with aromatic aldehyde in acetic acid/ammonium acetate afforded the dihydropyridine that was oxidized to the corresponding pyridine.

6,11-Dihydrodibenzo[b,e]thiepin-11-thiol and 11-acetic acid derivatives; Some 2-methyl-6,11-dihydrodibenzo[b,e]thiepins; Synthesis and pharmacological screening

1979 ◽  
Vol 44 (9) ◽  
pp. 2689-2701 ◽  
Author(s):  
Vladimír Valenta ◽  
František Kvis ◽  
Jiří Němec ◽  
Miroslav Protiva
Keyword(s):  
Acetic Acid ◽  
Zinc Chloride ◽  
Local Anaesthetic ◽  
Diethyl Malonate ◽  
Acetyl Derivative ◽  
Cardiovascular Activity ◽  
Starting Compound ◽  
Pharmacological Screening ◽  
Neurotropic Effects ◽  
Sodium Amide

11-Chloro-6,11-dihydrodibenzo[b,e]thiepin was transformed via the isothiourea V to the thiol IV which was used for the synthesis of aminoalkyl sulfides VII and VIII and of the methylpiperazide X. The same starting compound was used for alkylating diethyl malonate and via the intermediates XIV and XV, 6,11-dihydrodibenzo[b,e]thiepin-11-acetic acid (XVI) was obtained, which was converted to the methylpiperazide XVIII. Oxime XIX and 2-diethylaminoethylimine XX were prepared from 2-methyldibenzo[b,e]thiepin-11(6H)-one (II). Reduction of the ketone II afforded 2-methyl-6,11-dihydrodibenzo[b,e]thiepin (XII) giving by treatment with sodium amide and 3-dimethylaminopropyl chloride the amine XXIII. In the reaction of 6,11-dihydrodibenzo[b,e]thiepin-11-ol with sodium amide and 3-dimethylaminopropyl chloride, C-alkylation took place in addition to the expected etherification resulting in the diamine XXII. Reaction of phthalide with 4-aminothiophenol gave the acid XXIV which was transformed to the 3-dimethylaminopropyl ester XXV and N-acetyl derivative XXVI. Compound XXVI was cyclized with zinc chloride to the ketone III. Some of the compounds prepared exhibit structurally less specific peripheral and vegetative neurotropic effects (local anaesthetic, spasmolytic) and cardiovascular activity (antiarrhytmic).

Color Reactions of Rubber and Gutta-Percha

1929 ◽  
Vol 2 (2) ◽  
pp. 193-196
Author(s):  
F. Kirchhof
Keyword(s):  
Acetic Acid ◽  
Acetic Anhydride ◽  
Zinc Chloride ◽  
Trichloroacetic Acid ◽  
Acetyl Chloride ◽  
Oxidation Products ◽  
Arsenic Trichloride ◽  
Gutta Percha ◽  
Long Time ◽  
Color Reactions

Abstract THE present paper was suggested by a recent publication of Pauly on the same subject, who applied the well known sterol reactions of Hesse, Liebermann, Tschugajeff, etc., to the hydrocarbons of rubber and gutta-percha. These reactions depend either upon the action of concentrated H2SO4 on chloroform solutions of the substances in the presence or absence of acetic anhydride (Liebermann, Burchard and Hesse reactions) or other solvents, or condensation reagents are used, such as acetyl chloride and zinc chloride by Tschugajeff, and acetic acid with arsenic trichloride by Kahlenberg, and trichloroacetic acid with a trace of formaldehyde by Godoletz. All the known sterol reactions take place also with rubber or gutta-percha, with the appearance of intense red or violet colorations of varying stability, the color depending in part upon the quality and in part upon the purity of the samples. The Burchard reaction in particular is very sensitive in these respects. Thus with rubber purified with alkali by the Pummerer method, the color is a Bordeaux red which does not change for a long time, whereas solutions of unpurified rubber change rapidly, a change which is rightly ascribed by Pauly to relatively rapid oxidation in the presence of oxidation products in the case of the unpurified rubber.

scholarly journals Synthesis of Some Heterocyclic Compounds Derived from 2-Mercapto Benzoxazole

2013 ◽  
Vol 10 (3) ◽  
pp. 766-778 ◽  
Author(s):  
Baghdad Science Journal
Keyword(s):  
Acetic Acid ◽  
Melting Point ◽  
Heterocyclic Compounds ◽  
Nmr Spectra ◽  
Ring Closure ◽  
Phenyl Isothiocyanate ◽  
Triazole Derivative ◽  
Active Methylene Compounds ◽  
Ft Ir ◽  
Active Methylene

New series of 2-mecapto benzoxazole derivatives (1-20) incorporated into fused to different nitrogen and suphur containing heterocyclic were prepared from 2-meracpto benzoxazole, when treated with hydrazine hydrate to afford 2-hydrazino benzoxazol (1). Compound (1) converted to a variety of pyridazinone andphthalazinone derivatives (2-4) by reaction with different carboxylic anhydride. Also, reaction of (1) with phenyl isothiocyanate and ethyl chloro acetate afforded 3-phenyl-1,3-thiazolidin-2,4-dione-2-(benzoxazole-2-yl-hydrazone) (6). Azomethines (7-10) were prepared through reaction of (1) with aromatic aldehyde, then (7, 8) converted to thaizolidinone derivatives (11, 12). Treatment of (1) with active methylene compounds afforded derivative (13). Reaction of (1) with CS2 and NaOH gave 1,2,4-triazole derivative (14). Treatment of (1) with p-bromophenancyl bromide afforded another 1,2,4-triazole (15). The reaction of 2-mercapto benzoxazole with chloro acetic acid gave (16) followed by refluxing (16) with ortho-amino aniline giving benzimidazol (17). Moreover, the reaction of 2-mercapto benzoxazole with ethyl chloroacetate afforded (18), and then reaction of (18) with thiosemicarbazide and 4% NaOH leads to ring closure giving 1,2,4-triazole derivative (20). All compounds were confirmed by their melting point, FT-IR, UV-Vis spectra and 1H-NMR spectra for some of them.

scholarly journals Reaktionen von Derivaten der (Diphenylmethylen-amino)-essigsäure mit Schwefelkohlenstoff und Phenylisothiocyanat sowie Kristall- und Molekülstruktur des 2-(Diphenylmethylen-amino)-2-(1,3-dithian-2-yliden)-essigsäuremethylesters / Reactions of the Derivatives of (Diphenylmethylene-amino) Acetic Acid with Carbon Disulfide and Phenyl Isothiocyanate and Crystal and Molecular Structure of Methyl 2-(Diphenylmethylene-amino)-2-(1,3-dithiane-2-ylidene) Acetate

1993 ◽  
Vol 48 (4) ◽  
pp. 493-504 ◽  
Author(s):  
Wolfgang Dölling ◽  
Klaus Frost ◽  
Frank Heinemann ◽  
Helmut Hartung
Keyword(s):  
Molecular Structure ◽  
Acetic Acid ◽  
Carbon Disulfide ◽  
Structure Determination ◽  
Phase Transfer ◽  
Crystal And Molecular Structure ◽  
Phenyl Isothiocyanate ◽  
X Ray ◽  
Ketene Dithioacetals ◽  
Derivatives Of

Derivatives of (diphenylmethylene-amino) acetic acid 1-3 react in the presence of bases (NaH, t-BuONa) or under phase transfer conditions with carbon disulfide to give the corresponding ketene dithioacetals 4-11 after alkylation. Phenyl isothiocyanate and dicyclohexyl carbodiimide give rise to ketene-S,N- and N,N-acetals. Methyl 2-(diphenylmethyleneamino)-2-(1,3-dithiane-2-ylidene) acetate (7) was characterized by an X-ray structure determination. The compound has a 2-aza-1,3-butadiene fragment containing two well localized double bonds. The C=N-C=C group is significantly non-planar, the relevant torsion angle amounts to -103.5(3)°.

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