Formaldehyde → 6-Fluoro-3-((S)-4-methyl-morpholin-3-yl)-[1,2,4]triazolo[4,3-a]pyridine

Participants

Reaction Steps

To a solution of Intermediate 83b (297 mg, 0.92 mmol) in DCM (8.0 mL) at 0° C. was added TFA (400 μL) and the reaction stirred at RT overnight. Further TFA (600 μL) was added and the reaction stirred for 1 h then partitioned between DCM and sat. aq. NaHCO3 solution. The aqueous layer was then extracted with DCM (3×). The combined organic layers were washed with brine, dried (MgSO4), filtered and evaporated in vacuo. The residue was taken up in DCM (4.0 ml) and MeOH (3 drops) added. Formaldehyde solution (37 wt % in water, 162 μL, 2.00 mmol) was added followed by sodium triacetoxyborohydride (372 mg, 2.40 mmol). The reaction was stirred overnight then loaded onto an SCX-2 cartridge, which was washed with MeOH and eluted with 2M NH3 in MeOH; concentration in vacuo gave the title compound (75.0 mg, 34%). 1H NMR (400 MHz, d4-MeOD): 2.09 (3H, s), 2.49 (1H, td, J 11.4, 3.8), 2.98 (1H, dt, J 11.9, 2.0), 3.79-3.90 (3H, m), 3.94 (1H, m), 4.01 (1H, dd, J 10.1, 4.0), 7.50 (1H, ddd, J 10.0, 7.7, 2.2), 7.81 (1H, ddd, J 10.1, 4.9, 0.8), 8.98 (1H, ddd, J 4.0, 2.3, 0.8).

Provenance & Evidence