Sodium Bicarbonate → 1,1-Dimethylethyl (2,3-dihydro[1,4]dioxino[2,3-c]pyridin-7-ylmethyl)(1-{2-[3-(methyloxy)-6-oxopyrido[2,3-b]pyrazin-5(6H)-yl]ethyl}-4-piperidinyl)carbamate

Participants

Reaction Steps

A suspension of [3-(methyloxy)-6-oxopyrido[2,3-b]pyrazin-5(6H)-yl]acetaldehyde (185 mg 0.84 mmol) and 1,1-dimethylethyl (2,3-dihydro[1,4]dioxino[2,3-c]pyridin-7-ylmethyl)-4-piperidinylcarbamate (for a synthesis see WO2004/058144 Example 99(h) (283 mg, 0.84 mmol) in chloroform (10 mL) and methanol (1.5 mL) was stirred at room temperature under argon for 1 h before addition of sodium triacetoxyborohydride (515 mg, 2.52 mmol). The reaction was stirred at rt overnight. A saturated solution of sodium bicarbonate (20 mL) was added to the reaction and the aqueous phase was extracted with 10% MeOH/DCM (3×50 mL).The combined organic phases were dried (MgSO4), filtered and evaporated and the residue was subjected to column chromatography on silica gel eluting with 0-10% methanol-DCM to afford 252 mg of the title compound (60%).

Provenance & Evidence