Sodium Bicarbonate → tert-butyl (1-(2-(4-((cyclopropylamino)carbonyl)-7-methoxy-2-oxoquinolin-1-(2H)-yl)ethyl)piperidin-4-yl)(2,3-dihydro-1,4-benzodioxin-6-ylmethyl)carbamate

Participants

Reaction Steps

To 1.0 mL of methanol solution containing 0.13 g of N-cyclopropyl-7-methoxy-2-oxo-1-(2-oxoethyl)-1,2-dihydroquinoline-4-carboxamide, 0.16 g of tert-butyl (2,3-dihydro-1,4-benzodioxin-6-ylmethyl)(piperidin-4-yl)carbamate and 25 μL of acetic acid were added at room temperature and stirred at the same temperature for 1.5 hours. To the reaction mixture, 42 mg of sodium cyanoborohydride was added and stirred at the same temperature for 2 hours. Further, 42 mg of sodium cyanoborohydride was added and stirred at the same temperature for 2 hours and 15 min. 76 μL of acetic acid was added and stirred at the same temperature for 2 hours. To the mixture, aqueous saturated sodium hydrogen carbonate solution was added under ice-cooling to be adjusted to pH 8.7, 5.0 mL of methanol and 15 mL of chloroform were added, the organic layer was separated, and the aqueous layer was extracted with chloroform. The organic layer and extracts were combined, washed with aqueous saturated sodium chloride solution, dried over anhydrous magnesium sulfate, and the solvent was removed under reduced pressure. The residue thus obtained was purified by flash silica gel column chromatography [gradient elution of chloroform:methanol=100:0-70:30], to give 0.13 g of tert-butyl (1-(2-(4-((cyclopropylamino)carbonyl)-7-methoxy-2-oxoquinolin-1-(2H)-yl)ethyl)piperidin-4-yl)(2,3-dihydro-1,4-benzodioxin-6-ylmethyl)carbamate as a white foam.

Provenance & Evidence