An Ir photoredox catalyst-mediated highly site-selective direct alkylation and arylation of 2-pyridones has been developed. Under visible-light-promoted conditions, ethyl 2-bromo-2,2-difluoroacetate couples with various 2-pyridones exclusively at the C3 position. A similar photoredox catalysis is also effective for the direct C3-arylation with diaryliodonium triflates. Thus, these reactions occurs under very mild conditions (blue LEDs irradiation and ambient temperature) to form the corresponding C3-alkylated and arylated 2-pyridones of potential interest in medicinal and pharmaceutical chemistry.
KUBO KAZUO; ITO NORIKI; ISOMURA YASUO; SOZU ISAO; ARIMA HIDEKI; HOMMA HIR+, YAKUGAKU DZASSI, YAKUGAKU ZASSNI, J. PHARM. SOS. JAR., 1979, 99, NO 6, 58+