Microwave versus ultrasound assisted synthesis of some new heterocycles based on pyrazolone moiety

Journal of Saudi Chemical Society (Impact Factor: 1.29). 07/2010; 14(3):287-299. DOI: 10.1016/j.jscs.2010.02.010

ABSTRACT Different pyrazolone derivatives were prepared by microwave irradiation and ultrasound assisted methods besides the traditional ones. They were used for synthesis of some derivatives of spiropiperidine-4,4′-pyrano[2,3-c]pyrazole, dihydropyrano[2,3-c]pyrazole, pyrazole-4-carbothioamide, 4-(2-oxo-1,2-diphenylethylidene)-1H-pyrazol-5(4H)-one, azopyrazole, arylmethylenebis-1H-pyrazol-5-ol and araylidene-1H-pyrazol-5(4H)-one via reactions with different reagents applying the ultrasound method in some cases.

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