Formamide → 1-(4-Methyloxazol-5-yl)ethanone
Reaktionsgleichung
Cl[CH:2]([CH2:6][CH:7]=O)[C:3](=[O:5])[CH3:4].[CH:9]([NH2:11])=[O:10]>C(O)=O>[CH3:7][C:6]1[N:11]=[CH:9][O:10][C:2]=1[C:3](=[O:5])[CH3:4]Komponenten
4
Edukt 2
Produkt 1
Reagenzien, Katalysatoren, Lösungsmittel 1
Versuchsvorschrift
Scheme IX illustrates the synthesis of compounds represented by Formula XVI. Reaction of a mixture of 3-chloro-2,5-pentanedione and formamide in refluxing formic acid yields 4-methyl-5-acetyloxazole. Reaction of the sodium salt of 4-methyl-5-acetyloxazole and diethyl oxalate in ethanol affords the corresponding ketoacetate. Reaction of the ketoacetate with hydrazine in refluxing ethanol yields 3-ethoxycarbonyl-5-[4-(methyl)oxazol-5-yl]pyrazole which is alkylated to yield isomers XXIIa and XXIIb. Substituting triethyl orthoacetate for triethyl orthoformate in the reaction described in Scheme V yields isomeric compounds represented by. Formula XVIIa and XVIIb ##STR12##