Selective fluorination of ethyl 1-methylpyrazole-4-carboxylates with poly(hydrogen fluoride)-amine complex under electrolytic anodic oxidation
作者:Kenzi Makino、Hirosuke Yoshioka
DOI:10.1016/s0022-1139(00)81615-2
日期:1988.6
Fluorination of ethyl 1-methylpyrazole-4-carboxylate (1a) and its 3-chloro analogue (1b) with poly(hydrogen fluoride)-pyridine-triethylamine complex under electrolytic anodic oxidation yielded new ethyl 1-methyl-5-fluoropyrazole-4-carboxylate (2a), ethyl 1-fluoromethyl-5-fluoropyrazole-4-carboxylate (3a) and their 3-chloro analogues (2b) and (3b). Major factors controlling selectivities and yields