77435-41-7Relevant academic research and scientific papers
Study of the reactivity of α-acylenaminoketones. Synthesis of pyrazoles
Negri,Kascheres
, p. 109 - 123 (2007/10/03)
The reactions of 4-(methylamino)-3-penten-2-one with diazoketones yielded the α-acylenaminoketones 1-3 in good yields. Preparation of the α-acylenaminoketone 4 was carried out by treatment of 4-(t-butylamino)-3-penten-2-one with benzoyl chloride being followed by reaction of transamination with methylamine. The reactions were carried out in five different solvents and were submitted to gas chromatography/mass spectrometry analysis, with the goal of obtaining substituted pyrazoles and determining which of the carbonyls would preferentially be attacked by the nucleophile. The reactions of compounds 1-4 with hydrazine reagents led to the formation of the pyrazoles 5-7a-q. Small amounts of 4-methylamino-2-pentenones 10a-q, amides 11a-q and pyrazoles 12a-q were also obtained in these reactions. The unexpected formation of pyrazoles 15d,h,q was detected when methanol and N,N-dimethylformamide were used as solvents in the reactions of α-acylenaminoketone 4 with hydrazine reagents.
Synthesis of 4-Acyl- and 4-Alkoxy-carbonylpyrazoles
Al-Saleh, Fowzia S.,Khawaja, Ibtisam K. Al,Joule, John A.
, p. 642 - 645 (2007/10/02)
N'-Aroyl- or N'-acetyl, N'-phenyl- or N'-methyl-hydrazino-derivatives (1) of 1,3-dicarbonyl compounds can be converted by mild base treatment into 5-aryl- or 5-methyl-, 1-phenyl- or 1-methylpyrazoles carrying an acyl or alkoxycarbonyl group at C-4.
