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

To a solution of 0.12 g of (3-methoxy-6-oxopyrido(2,3-b)pyrazin-5(6H)-yl)acetaldehyde in 5 mL of methylene chloride, 0.18 g of tert-butyl (2,3-dihydro(1,4)dioxino(2,3-c)pyridin-7-ylmethyl)(piperidin-4-yl)carbamate, 26 μL of acetic acid and 0.12 g of sodium triacetoxyborohydride were added, and the mixture was stirred at room temperature for 2 hours 30 minutes. To the reaction mixture, a saturated aqueous sodium hydrogen carbonate solution and chloroform were added, the organic layer was separated, and the aqueous layer was extracted with chloroform. The organic layer and the extract were combined, the resultant solution was washed with a saturated aqueous sodium chloride solution and dried over anhydrous magnesium sulfate, and the solvent was distilled off under reduced pressure. The resultant residue was purified by silica gel column chromatography using an eluent of chloroform:methanol=20:1 to obtain 0.32 g of tert-butyl (2,3-dihydro(1,4)dioxino(2,3-c)pyridin-7-ylmethyl)(1-(2-(3-methoxy-6-oxopyrido(2,3-b)pyrazin-5(6H)-yl)ethyl)piperidin-4-yl)carbamate as a colorless oily substance.

Provenance & Evidence