Fluoro-containing 4-ethylidene-2,4-dihydropyrazol-3-ones in the Diels-Alder reaction with cyclopentadiene and cyanamines
摘要:
The fluorinated 4-ethylidene-2,4-dihydropyrazol-3-ones act as heterodienes and dienophiles in the Diels-Alder reaction with amines and cyclopentadiene to give 1,4-dihydropyrazolo[4,3-e]-1,3-oxazines and spirobicyclo[2.2.1]hept-5-ene-2,4'-pyrazolones, respectively.