76877-98-0Relevant academic research and scientific papers
Modifications and Extensions of the Pschorr Reaction in Pyrazole Series. Access to the Benzopyranopyrazole System of Pharmaceutical Interest
Daidone, Giuseppe,Plescia, Salvatore,Maggio, Benedetta,Sprio, Vincenzo,Benetollo, Franco,Bombieri, Gabriella
, p. 285 - 292 (2007/10/02)
The Pschorr reaction performed under non-classical reaction conditions on the diazonium chloride derived from 2-amino-N-methyl-N-(3-methyl-1-phenyl-1H-pyrazol-5-yl)benzamide 1 afforded the epimers (3'R,4'S)- and (3'R,4'R)-4'-chloro-2',4'-dihydro-2,5'-dime
Studies on the Synthesis of Heterocyclic Compounds. Part IV. Further Investigation of the Pschorr Reaction with Some Pyrazole Derivatives
Daidone, Giuseppe,Plescia, Salvatore,Fabra, Jole
, p. 1409 - 1411 (2007/10/02)
Thermal decomposition of the diazonium sulfate derived from N-methyl-(1-phenyl-3-methylpyrazol-5-yl)-2-aminobenzamide afforded products formulated as 1-phenyl-3-methylbenzopyranopyrazol-5-one (yield 10percent), 1,4-dimethyl-3-phenylpyrazoloisoquinolin-5-one (yield 10percent), N-methyl-(1-phenyl-3-methyl-pyrazol-5-yl)-2-hydroxybenzamide (yield 8percent) and 4'-hydroxy-2,3'-dimethyl-1'-phenylspiro-pyrazolin>-3-one (yield 20percent).Decomposition of the diazonium sulfate derived from N-methyl-(1,3-diphenyl-pyrazol-5-yl)-2-aminobenzamide gave products formulated as 7,9-dimethyldibenzopyrazolo-diazocin-10-(9H)one (yield 8percent), 4-methyl-1,3-diphenylpyrazoloisoquinoline-5-one (yield 7percent) and 4'-hydroxy-2-methyl-1',3'-diphenylspiropyrazolin>-3-one (yield 10percent).The spiro compounds 6a,b underwent thermal and acid-catalysed conversion into the hitherto unknown 2-benzopyranopyrazole ring system 7a,b in good yield.Analytical and spectral data are presented which supported the structures proposed.
