Synthesis of Pyrazolo[3,4-

Journal of the Korean Chemical Society

Ho Sik Kim¹  Hyung Chul Lee¹ 

关键词: Pyrazolo[3;    4-b]quinoxalines;   

DOI  :  

学科分类：化学（综合）

来源: Korean Chemical Society

【 摘 要 】

The reaction of 3-methoxycarbonylmethylene-2-oxo-1,2,3,4-tetrahydroquinoxaline (11) with p-fluorobenzenediazonium chloride gave 3-[a-(p-fluorophenylhydrazono)methoxycarbonylmethyl]-1,2-dihydro-2-oxoquinoxaline (12), whose reaction with phosphoryl chloride provided 2-chloro-3-[a-(p-fluorophenylhydrazono)- methoxycarbonylmethyl] quinoxaline (13). The reaction of compound 13 with hydrazine hydrate resulted in the intramolecular cyclization to give 1-(p-fluorophenyl)-3-hydrazinocarbonyl-1H-pyrazolo[3,4-b]quinoxaline (14). The reaction of compound 14 with alkanoyl chlorides, benzoyl chlorides, benzaldehydes or isothiocyanates afforded 1H-pyrazolo[3,4-b]quinoxalines 15-18, respectively. Refluxing of compound 18 in 2N NaOH solution gave the 1,2,4-triazolyl-1H-pyrazolo[3,4-b]quinoxaline (19). The reaction of compounds 17 and acetic anhydride gave the cyclized compounds, 1,3,4- oxadiazolyl-1H-pyrazolo[3,4-b]quinoxalines (20).

【 授权许可】

Unknown