反应详情

Spiro[4H-3,1-benzoxazine-4,4′-piperidin]-2(1H)-one (A4) (22 mg, 0.10 mmol) was dissolved in anhydrous 1,2-dichloroethane (750 μL) in a scintillation vial and treated with 3-methylbutanal (va) (9 mg, 0.10 mmol), followed by sodium triacetoxyborohydride (30 mg, 0.14 mmol). The reaction was stirred at room temperature for 1 hour, then quenched with methanol (500 μL) and stirred at room temperature for an additional 30 minutes. The reaction was filtered (Whatman 0.45 μm PTFE) and subjected to reverse-phase HPLC purification [2-99% CH3CN gradient over 13 min with 0.1% TFA (aq), 35 mL/min, 1.0 mL injected] to provide 1′-isopentylspiro[benzo[d][1,3]oxazine-4,4′-piperidin]-2(1H)-one (compound no. 76). LC/MS m/z 289.0 [M+H]+, retention time 1.55 min (RP-C18, 10-99% CH3CN/0.05% TFA).

1. customquenched with methanol (500 μL)
2. stirringstirred at room temperature for an additional 30 minutes
3. filtrationThe reaction was filtered (Whatman 0.45 μm PTFE)
4. customsubjected to reverse-phase HPLC purification [2-99% CH3CN gradient over 13 min with 0.1% TFA (aq), 35 mL/min, 1.0 mL injected]