反应详情

A suspension of 1,4-dioxa-9-aza-dispiro[4.2.4.2]tetradecan-10-one (prepared according to J. Org. Chem. 2004, 69, 2755) (500 mg, 2.4 mmol) in THF (7 mL) was treated with 1M aqueous HCl (7 mL) and the resulting mixture stirred at ambient temperature for 20 hours. The reaction mixture was quenched with 1M aqueous NaOH (7 mL) and the mixture concentrated under vacuum. The resulting solid was purified by column chromatography on silica gel (gradient: DCM then 2 to 10% methanol in ethyl acetate) to afford 398 mg (quant.) of 1-aza-spiro[4.5]decane-2,8-dione. LCMS (Method B, ESI): RT=1.63 min, 168; 1H NMR (400 MHz, CDCl3) δ: 3.95 (s, 1H), 3.77-3.71 (m, 1H), 2.46-2.44 (m, 3H), 2.05-2.03 (m, 3H), 1.81-1.65 (m, 4H).

1. customThe reaction mixture was quenched with 1M aqueous NaOH (7 mL)
2. concentrationthe mixture concentrated under vacuum
3. customThe resulting solid was purified by column chromatography on silica gel (gradient