Nitric Acid → (R)-5-(2-fluoro-5-nitro-phenyl)-5-methyl-1,1-dioxo-1,2,5,6-tetrahydro-1lambda6-[1,4]thiazin-3-ylamine

Participants

Reaction Steps

To a solution of (R)-5-(2-fluoro-phenyl)-5-methyl-1,1-dioxo-1,2,5,6-tetrahydro-1λ6-[1,4]thiazin-3-ylamine (497 mg, 1.94 mmol, Eq: 1.00) in conc. sulfuric acid (14.8 g, 8.06 ml, 151 mmol, Eq: 78) was added at 0° C. 100% nitric acid (189 mg, 134 μl, 3.01 mmol, Eq: 1.55) and the mixture was stirred at 0° C. for 1 hour. Poured into sat NaHCO3-sol., extracted with ethyl acetate, the organic layer was dried over Na2SO4. Removal of the solvent in vacuum left the (R)-5-(2-fluoro-5-nitro-phenyl)-5-methyl-1,1-dioxo-1,2,5,6-tetrahydro-1λ6-[1,4]thiazin-3-ylamine (584 mg, 1.94 mmol, 100% yield) as a light yellow oil. MS (ISP): m/z=302.1 [M+H]+.

Provenance & Evidence