4-Methylmorpholine → HCID 22176271, compound

Participants

Reaction Conditions

Reaction Steps

To a solution of 4-butoxy-3-{{(tert-butoxycarbonyl)-amino}methyl}-2-isobutyl-1-oxo-1,2-dihydro-6-isoquinolinecarboxylic acid (synthesized according to the method similar to that in Example 76 (1)) (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 was added sodium tetrahydroborate (0.11 g, 3 mmol) 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 residue was recrystallized from ethyl acetate-diisopropyl ether to give tert-butyl(4-butoxy-6-hydroxymethyl-2-isobutyl-1-oxo-1,2-dihydro-3-isoquinolinyl)methylcarbamate (0.33 g, 76.7%) as crystals.

Provenance & Evidence