23768-90-3Relevant academic research and scientific papers
Synthesis of 4-hydroxylamino-1-azabuta-1,3-dienes and their cyclization to 2-substituted pyrazole 1-oxides
Alcazar, Jesus,Almena, Ines,Begtrup, Mikael,Hoz, Antonio de la
, p. 2773 - 2782 (2007/10/02)
2-Aromatic or 2-aliphatic substituted pyrazole 1-oxides with substituents at the 3-, 4- or 5-position have been prepared from β-dicarbonyl compounds or ketones.The β-dicarbonyl compounds were treated with p-toluidine to give 1,5-di-p-tolyl-1,5-diazapenta-1,3-dienium salts in which the p-tolyimino groups can be converted into alkylimino groups by treatment with aliphatic amine.Subsequent deprotonation and treatment with O-tert-butyldimethylsilylhydroxylamine produced 4-arylamino- or 4-alkylamino-1-tert-butyldimethylsilyloxy-1-azabuta-1,3-diene.The tautomeric structure, the configuration and the conformation of the dienes were elucidated by 1H and 13C NMR spectroscopy.Oxidation of the alkylamino-1-tert-butyldimethylsilyloxy-1-azabuta-1,3-dienes with copper(II) ions led to cyclization with formation of pyrazole 1-oxides.These could be prepared by oxidation of 3-amino oximes obtained from ketones through aminoalkylation at the α-position and treatment with hydroxyammonium chloride.If 1,5-diaryl-1,5-diazapenta-1,3-diene was treated with O-(p-tolylsulfonyl)hydroxylamine spontaneous cyclization occurred to give 1-(p-tolyl)pyrazole.
Hydrolysis of Aryl Derivates of Malonaldehyde Dianil. III
Ono, Machiko,Tamura, Shinzo
, p. 1453 - 1462 (2007/10/02)
The reaction sequence of hydrolysis of N-acyl derivates of malonaldehyde dianil was examined.Hydrichloric acid-catalysed hydrolysis occured at the imino group to form arylamine and β-(N-acylarylamino)acrolein; the latter compound is not stable in acid solution.In the case of 1-(N-phenylcarbamoyl-p-methylphenylamino)-3-(p-methylphenylimino)-1-propene, hydrolysis occured at both the imino and the carbamoyl groups.Buffer catalysed hydrolysis occured at the imino group, and the resulting β-(N-acylarylamino)acrolein and arylamine reacted to form β-arylaminoacrolein and N-arylamine.The aminolysis reaction was suppressed in hydrochloric acid-catalysed hydrolysis.Alkaline hydrolysis of N-acyl derivates of malonaldehyde dianil and of β-arylaminoacrolein occured at the amide carbonyl group except in the case of 1-(N-tosyl-p-methylphenylamino)-3-(p-methylphenylimino)-1-propene.N-tosyl-p-toluidine was obtained in this case.Keywords--hydrolysis; malonaldehyde dianil; β-arylaminoacrolein; 1-(N-acylarylamino)-3-arylamino-1-propene; β-(N-acylarylamino)acrolein; 1-(N-tosyl-p-methylphenyilamino)-3-(p-methylphenylimino)-1-propene; 1-(N-tosyl-p-methylphenylamino)-3-(p-methylphenyilimino-1-butene; β-(N-tosyl-p-toluidino)acrolein; 4-(N-tosyl-p-toluidino)-3-buten-2-one
Hydrolysis of Acyl Derivates of Malonaldehyde Dianil. II. Aminolysis and Alcoholysis of Acyl Derivates of Malonaldehyde Dianil and β-Arylaminoacrolein
Ono, Machiko,Tamura, Shinzo
, p. 1443 - 1452 (2007/10/02)
Aminolysis and alcoholysis reactions of β-arylaminoacrolein and its N-acyl derivates were studied.Acid-catalysed aminolysis of β-(N-benzoyl-p-toluidino)acrolein (III) occured at the β-position of III, accompanying the reversible interaction of the amine and the formyl group of III.In the reaction of III and amine in methanol under neutral conditions, aminolysis at the β-position of III and alcoholysis of the amide carbonyl group of III proceeded in parallel; the latter reaction was catalysed by amine.In either case, no evidence of aminolysis at the amide carbonyl group of III was obtained.The reaction of the fotmyl group of III proceeded mainly when III and amine were reacted in benzene solution.Thus, 1-(N-benzoyl-p-methylphenylamino)-3-(p-chlorophenylimino)-1-propene (XII) was obtained when III and p-chloroaniline were reacted in benzene.Alkaline hydrolysis of XII afforded 1-(p-methylphenylamino)-3-(p-chlorophenylimino)-1-propene (XIII), an unsymmetrical malonaldehyd dianil.Aminolysis and alcoholysis reactions of 1-arylamino-3-arylimino-1-propene(malonaldehyde dianil) and its N-acyl-derivates were also studied.Alcoholysis occured at the amide carbonyl group of N-acyl derivates, while aminolysis occured at the 1-position except for the case of 1-(N-phenylcarbamoyl-p-methylphenylamino)-3-(p-methylphenylimino)-1-propene (XIV).Keywords--aminolysis; alcoholysis; β(N-benzoyl-p-toluidino)acrolein; β-(N-phenycarbamoyl-p-toluidino)acrolein; l-(N-benzoyl-p-methylphenylamino)-3-(p-methylphenylimino)-1-propene; l-(N-benzoyl-p-methylphenylamino)-3-(chlorophenylimino)-1-propene; 1-(p-methyphenylamino)-3-(p-chlorophenylimino)-1-propene; 1-(N-phenylcarbamoyl-p-methylphenylamino)-3-(p-methylphenylamino)-3-(p-methylphenylimino)-1-propene
Hydrolysis of Acyl Derivatives of Malonaldehyde Dianil. IV. Preparation of β-(p-Toluidino)crotonaldehyde
Ono, Machiko,Tamura, Shinzo
, p. 1463 - 1472 (2007/10/02)
β-(p-Toluidino)crotonaldehyde (V), a possible reactant of the Combes reaction, was prepared by the alkaline hydrolysis of β-N-(p-chlorobenzoyl)-p-toluidinocrotonaldehyde (XXIV).Compound XXIV was prepared by the hydrochloric acid-catalyzed hydrolysis of 3-
