We found a match
Your institution may have access to this item. Find your institution then sign in to continue.
- Title
A Novel Synthesis of Some 1,4-Phenylene-bis-heterocyclic Derivatives and of Some Pyran, Pyrano[2,3-c]pyrazole, and Pyrano[2,3-d]pyrimidine Derivatives.
- Authors
Abdelrazek, F. M.; Helal, M. H.; Hebishy, A. S.; Hassan, S. M.
- Abstract
p-Diacetyl benzene 1 undergoes to afford p-bromoacetyl phenacyl bromide 2. Compound 2 reacts with twofold excess of malononitrile to afford 2-{2-[4-(3,3-Dicyanopropionyl)-phenyl]-2-oxo-ethyl}-malononitrile 3. Compound 3 could be cyclized to afford the 1,4-phenylene-bis-furan derivative 4. Compound 3 reacts also with a twofold excess of hydrazine hydrate and phenyl hydrazine under dry conditions at RT to afford the bis-pyrazole derivatives 5a, 5b, respectively. The reaction of 5a, 5b with the same reagents in refluxing dioxane afforded the bis-pyrazolopyridazine derivatives 7a, 7b, respectively. The azo coupling of compound 3 with arene diazonium salts afforded the bis-pyrazole derivatives 9a, 9b, 9c. The β-keto esters 10a, 10b react with benzaldehyde and malononitrile in a one pot synthesis to afford the pyran derivatives 11a, 11b. These latter compounds react with hydrazine hydrate and to afford the pyrano[2,3-c]pyrazoles 15a, 15b and the pyrano[2,3-d]pyrimidine derivatives 17a, 17b, respectively.
- Subjects
PHENYLENE compounds synthesis; HETEROCYCLIC compound derivatives; PYRAN synthesis; BENZENE compounds; PYRAZOLES; PYRIMIDINE derivatives
- Publication
Journal of Heterocyclic Chemistry, 2015, Vol 52, Issue 4, p1026
- ISSN
0022-152X
- Publication type
Article
- DOI
10.1002/jhet.2089