106089-55-8Relevant academic research and scientific papers
Synthesis of Pyranopyrazol-4(1H)-ones and -4(2H)-ones from Dehydroacetic Acid. Homo- and Heteronuclear Selective NOE Measurements for Unambiguous Structure Assignment
Cantos, Albert,March, Pedro de,Moreno-Manas, Marcial,Pla, Anna,Sanchez-Ferrando, Francisco,Virgili, Albert
, p. 4425 - 4432 (2007/10/02)
Cyclization of dehydroacetic acid N-substituted hydrazones furnished 1-substituted 3,6-dimethylpyranopyrazol-4(1H)-ones, together with varying amounts of N,N'-disubstituted 5-hydroxy-3-methyl-4-(3-methyl-1H-pyrazol-5-yl)-1H-pyrazoles.The same pyranopyrazolones were obtained regioselectively without side reactions from N-alkylhydrazines and 4-chloro-3-(1-chlorovinyl)-6-methyl-2H-pyran-2-one, ("Dehydroacetchlorid"), while N-arylhydrazines gave the 2-aryl-3,6-dimethylpyranopyrazol-4(2H)-ones.NMR NOE methods, including long-range selective heteronuclear 13C NOE enhancement measurements, allowed unambiguous between -4(1H)-ones and -4(2H)-ones.
SYNTHESIS AND UNAMBIGUOUS ASSIGNMENT OF STRUCTURE TO PYRANOPYRAZOL-4(1H)-ONES AND -4(2H)-ONES
Cantos, Albert,March, Pere De,Moreno-Manas, Marcial,Pla, Anna,Sanchez-Ferrando, Francisco,Virgili, Albert
, p. 295 - 298 (2007/10/02)
A clean synthesis of pyranopyrazolones is described.The reactions of 4-chloro-3-(1-chlorovinyl)-6-methyl-2-pyrone with arylhydrazines give pyranopyrazol-4(2H)-ones as the only identified products.However, the isomeric pyranopyrazol-4(1H)-one
