Chemistry Department, Faculty of Science, Cairo University, Giza 12613, Giza, Egypt
Wael A. A. Arafa
Department of Chemistry, College of Science, Jouf University, Sakaka 72341, Al Jouf, Saudi Arabia
Ahmed I. Abd-Elhamid
Composites and Nanostructured Materials Research Department, Advanced Technology and New Materials Research Institute, City of Scientific Research and Technological Applications (SRTA-City), New Borg Al-Arab 21934, Alexandria, Egypt
Ismail M. Ahmed
Department of Chemistry, College of Science, Jouf University, Sakaka 72341, Al Jouf, Saudi Arabia
Mohamed A. Abdelgawad
Department of Pharmaceutical Chemistry, College of Pharmacy, Jouf University, Sakaka 72341, Al Jouf, Saudi Arabia
Hazim M. Ali
Department of Chemistry, College of Science, Jouf University, Sakaka 72341, Al Jouf, Saudi Arabia
Ibrahim Hotan Alsohaimi
Department of Chemistry, College of Science, Jouf University, Sakaka 72341, Al Jouf, Saudi Arabia
An appropriate and efficient Q-tube-assisted ammonium acetate-mediated protocol for the assembly of the hitherto unreported 5-arylazopyrazolo[3,4-b]pyridines was demonstrated. This methodology comprises the cyclocondensation reaction of 5-amino-2-phenyl-4H-pyrazol-3-one with an assortment of arylhydrazonals in an NH4OAc/AcOH buffer solution operating a Q-tube reactor. This versatile protocol exhibited several outstanding merits: easy work-up, mild conditions, scalability, broad substrate scope, safety (the Q-tube kit is simply for pressing and sealing), and a high atom economy. Consequently, performing such reactions under elevated pressures and utilizing the Q-tube reactor seemed preferable for achieving the required products in comparison to the conventional conditions. Diverse spectroscopic methods and X-ray single-crystal techniques were applied to confirm the proposed structure of the targeted compounds.
