Electrolytic partial fluorination of organic compounds. 31. Regioselectiveanodic fluorination of 2-quinolyl and 4-(7-trifluoromethyl)quinolyl sulfides and the factors affecting its optimization
Km. Dawood et T. Fuchigami, Electrolytic partial fluorination of organic compounds. 31. Regioselectiveanodic fluorination of 2-quinolyl and 4-(7-trifluoromethyl)quinolyl sulfides and the factors affecting its optimization, J ORG CHEM, 64(1), 1999, pp. 138-143
Electrochemical fluorination of 2-quinolyl and 4-(7-trifluoromethyl)quinoly
l sulfides bearing an electron-withdrawing group at the position alpha to t
he sulfur atom was studied. Fluorination was successfully carried out using
Et4NE . nHF (n = 3, 4) and Et3N . 3HF as a supporting electrolyte and a fl
uoride ion source in dimethoxyethane in a divided cell to provide the corre
sponding alpha-fluorinated sulfides in good yields. A trifluoromethyl group
positioned on the quinoline ring significantly enhanced anodic alpha-fluor
ination. 4-(Methylthio)-7-(trifluoromethyl)quinoline was also found to unde
rgo anodic fluorination efficiently. Solvent effects of various donor numbe
rs were also established.