4-Methylmorpholine → HCID 22175957, compound

Participants

Reaction Conditions

Reaction Steps

To a solution of 4-butoxy-3-[[(tert-butoxycarbonyl)amino]methyl]-2-cyclopropylmethyl-1-oxo-1,2-dihydro-6-isoquinolinecarboxylic acid (Example 146 (9)) (0.45 g, 3.5 mmol) and N-methylmorpholine (0.13 mL, 1.2 mmol) in tetrahydrofuran (10 mL) was added ethyl chloroformate (0.12 mL, 1.2 mmol) at 0° C. and the mixture was stirred at 0° C. for 10 min. To the obtained mixture were added sodium tetrahydroborate (0.11 g, 3 mmol) and methanol (5 mL), and the mixture was stirred at 0° C. for 1 h. The reaction mixture was poured into water and extracted with ethyl acetate. The extract was washed with brine, dried over anhydrous magnesium sulfate and concentrated under reduced pressure. The precipitated crystals were recrystallized from ethyl acetate-diisopropyl ether to give tert-butyl(4-butoxy-2-cyclopropylmethyl-6-hydroxymethyl-1-oxo-1,2-dihydro-3-isoquinolinyl)methylcarbamate (0.33 g, 76.7%) as crystals.

Provenance & Evidence