Article ID | Journal | Published Year | Pages | File Type |
---|---|---|---|---|
1411341 | Journal of Molecular Structure | 2009 | 7 Pages |
Abstract
3(5)-Amino-5(3)-hydrazinopyrazole dihydrochloride (8) reacts with pentane-2,4-dione (9a) to afford 2-(3â²,5â²-dimethylpyrazol-1â²-yl)-5,7-dimethylpyrazolo[1,5-a]pyrimidine (10a) instead of the 3-(3â²,5â²-dimethylpyrazol-1â²-yl)-4,6-dimethyl-1H-pyrazolo[3,4-b]pyridine isomer (11). Similarly, the reaction of 8 with phenyl-1,3-butanedione (9b) resulted into the formation of 2-(3â²-methyl-5â²-phenylpyrazol-1â²-yl)-5-methyl-7-phenylpyrazolo[1,5-a]pyrimidine (10b) out of the four possible regioisomers. The structure of the reaction products 10a and b was established by analysis of high-resolution 1H NMR spectra. Complete spectral analysis has been achieved utilizing (1H-13C) HMQC as well as (1H-13C) and (1H-15N) HMBC experiments.
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Physical Sciences and Engineering
Chemistry
Organic Chemistry
Authors
Ranjana Aggarwal, Garima Sumran, Rosa M. Claramunt, Dionisia Sanz, J. Elguero,