Abstract
The catalytic performance of Preyssler, H14[NaP5W30O110]: Wells–Dawson, H6[P2W18O62]; and Keggin, H3[PW12O40] and H4[PMo11VO40], heteropolyacids as pure compounds have been studied in the synthesis of pyrazoles and diazepines in the condensation of hydrazines, hydrazides, and diamines with various 1,3-diketones. In all cases the best yields were obtained using H14[NaP5W30O110].
GRAPHICAL ABSTRACT
ACKNOWLEDGMENTS
The authors are thankful to the Agricultural Researches and Services Center, Mashhad, Feyzabad, Iran; Mashhad Islamic Azad University and Chemistry Department, University of Oslo, Norway and National Research Council Canada for support of this work.
Notes
a Yields are analyzed by GC.
b The reactions are carried out in water as solvent and at room temperature.
a Yields are analyzed by GC.
b The reactions are carried out in water as solvent and at room temperature.
a Yields are analyzed by GC.
b The reactions are carried out in water as solvent and at room temperature.
a Yields are analyzed by GC.
b The reactions are carried out in water as solvent and at room temperature.
a Isolated yields.
a Isolated yields.
a Isolated yields.
a Isolated yields.
a , b Isolated yields and yields obtained in the first, second, third, fourth and fifth reuse of the catalyst.
a Yield of 3,5-dimethyl-1-phenyl-1H-pyrazole.
b Yield of 2,4-dimethyl-3H-1,5-benzodiazepine.