RESUMO
Claisen-Schmidt condensation reaction of 4-acetamidoacetophenone with aromatic aldehydes under ultrasonic irradiation affords acetylaminochalcones (yields: 71-90%) which also under ultrasonic irradiation and in the presence of sodium acetate and acetic acid aqueous undergo facile and clean cyclocondensation with hydrazine to afford 3-(4-acetamidophenyl)-5-(aryl)-1-H-pyrazolines. The pyrazolines were obtained in good to excellent yields (81-89%), and were characterized by conventional spectral data. The work-up is simple and the results obtained indicate that, unlike classical heating, ultrasonic irradiation results in higher yields, shorter reaction times (1.5-2.3 h) and milder conditions.
Assuntos
Pirazóis/síntese química , Sonicação , Estrutura Molecular , Pirazóis/químicaRESUMO
The title compound, C(23)H(32)Cl(2)N(2)O(2), a potential chiral ligand for coordination chemistry, was prepared by a two-step reaction. The mol-ecule is located on a crystallographic centre of inversion. As a result, the methyl group bonded to the methyl-ene group is disordered over two equally occupied positions, sharing the same site as the H atom of the chiral C atom. As a further consequence of the crystallographic centrosymmetry, the 1,2-diamino-propane unit adopts an anti-periplanar conformation and the two benzene rings are coplanar. The central chain is in an all-trans arrangement. An intra-molecular O-Hâ¯N hydrogen bond makes an S(6) ring motif. A C-Hâ¯π inter-action links the mol-ecules into one-dimensional chains along the [001] direction.
RESUMO
A series of pyrimido[4,5-b]quinolines (5-deazaflavines), were synthesized by microwave assisted intramolecular cyclization. The N4-substituted-2,4-diamino-6-chloro-pyrimidine-5-carbaldehydes, were prepared by selective monoamination of 2-amino-4,6-dichloropyrimidine-5-carbaldehyde with aliphatic and aromatic amines.