Methyl 3-fluoro-4-(2-(5-nitropyridin-2-ylamino)thiazol-5-ylthio)picolinate → Methyl 4-(2-(5-aminopyridin-2-ylamino)thiazol-5-ylthio)-3-fluoropicolinate

Participants

Reaction Steps

A stirring solution of methyl 3-fluoro-4-(2-(5-nitropyridin-2-ylamino)thiazol-5-ylthio)picolinate (1.77 g, 4.34 mmol), 10% Pt/C (366 mg) in acetic acid (5 mL) and THF (20 mL) was purged 4× with H2, then pressurized to 140 psi in a steel bomb reactor and stirred overnight. The reaction was depressurized, and LCMS showed intermediate nitroso as predominant product. Pt/C (270 mg) was added and the reaction repressurized to 140 psi and stirred overnight. The reaction was depressurized, LCMS showed complete reaction. The reaction was filtered through Celite, washed with THF and DCM, the filtrate was concentrated. The residue was recrystallized from EtOAc and hexane, the solid was collected by filtration and washed with hexane. The product was obtained (828 mg, 51%) as a solid: 1H NMR (400 MHz, DMSO-d6) δ ppm: 11.43 (1H, s), 8.31 (1H, d, J=5.05 Hz), 7.72 (1H, s), 7.66 (1H, d, J=2.27 Hz), 7.11 (1H, t, J=5.31 Hz), 7.06 (1H, dd, J=8.59, 2.78 Hz), 6.87 (1H, d, J=8.59 Hz), 4.99 (2H, s), 3.89 (3H, s); LC/MS (M+H)+: 378. HPLC ret. time (Condition E): 1.45 min.

Provenance & Evidence