(3R)-3-ethyl-7-fluoro-4-(4-hydroxybenzoyl)-1-methyl-3,4-dihydroquinoxalin-2(1H)-one → (3S)-1,3-diethyl-6-fluoro-4-(4-hydroxybenzoyl)-3,4-dihydroquinoxalin-2(1H)-one

Participants

Reaction Steps

(3S)-1,3-Diethyl-6-fluoro-4-(4-methoxybenzoyl)-3,4-dihydroquinoxalin-2(1H)-one was treated according to the procedure for the preparation of (3R)-3-ethyl-7-fluoro-4-(4-hydroxybenzoyl)-1-methyl-3,4-dihydroquinoxalin-2(1H)-one (see Example 1) to yield (3S)-1,3-diethyl-6-fluoro-4-(4-hydroxybenzoyl)-3,4-dihydroquinoxalin-2(1H)-one (93%). [α]D25=+295° (c=0.0098 G/ML, CHCl3); MS (ESI) m/z 343 ([M+H]+); MS (ESI) m/z 341 ([M−H]−); HRMS: calcd for C19H19FN2O3, 342.1380; found (ESI_FT), 343.14475.

Provenance & Evidence