Thiomorpholine, 4-(2,6-difluoro-4-nitrophenyl)-, 1,1-dioxide → 4-(4-Amino-2,6-difluorophenyl)-1lambda~6~,4-thiazinane-1,1-dione

Participants

Reaction Steps

To an autoclave is added 4-(2,6-difluoro-4-nitrophenyl)thiomorpholine 1,1-dioxide (Step 2, 7.0 kg, 24 moles, 1.0 eq). Raney Nickel (1.4 kg) is activated and suspended in tetrahydrofuran (4 L), and the slurry is added to the autoclave followed by additional tetrahydrofuran (66 L). The mixture is heated at 40° C. under a 40 psi hydrogen atmosphere until the reaction is complete. The mixture is then filtered, and the filtrate is directly used in the next step. A small portion of the filtrate can be concentrated and recrystallized in isopropanol to give the title compound in pure form, 1H NMR (DMSO-d,) δ 6.17 (m, 2H), 5.35 (s, 2H), 3.32 (m, 4H), 3.15 (m, 4H).

Provenance & Evidence