反应详情

温度

-78 °C

To a −78° C. solution of methyl 7-methyl-3-neopentyl-2-oxo-1-oxa-3-azaspiro[4.5]decane-7-carboxylate (24.2 g, 82.0 mmol) in THF (204 mL) under N2 was slowly added lithium aluminium hydride, 1 M in THF (122 mL, 122 mmol). After stirring 1 h at −78° C., additional lithium aluminum hydride, 1 M in THF (0.061 mL, 61.0 mmol) was added. After 3 h the reaction was quenched with water (5 mL) and diluted with 4 N HCl (500 mL). The product was extracted into EtOAc (3×300 mL). The combined organics were dried over MgSO4, filtered, and concentrated onto florisil for purification on a 330 g silica gel column (10-50% EtOAc/hexanes, 30 min gradient; 50% EtOAc/hexanes, 15 min; 50-75% EtOAc/hexanes, 10 min gradient; 75% EtOAc/hexanes, 10 min; 100 mL/min elution; 254 nm detection) to provide the title compound (14.7 g) as an orange oil and the intermediate aldehyde product (7.19 g) as a yellow solid.

1. customTo a −78° C.
2. customAfter 3 h the reaction was quenched with water (5 mL)
3. additiondiluted with 4 N HCl (500 mL)
4. extractionThe product was extracted into EtOAc (3×300 mL)
5. dry with materialThe combined organics were dried over MgSO4
6. filtrationfiltered
7. concentrationconcentrated onto florisil for purification on a 330 g silica gel column (10-50% EtOAc/hexanes, 30 min gradient; 50% EtOAc/hexanes, 15 min; 50-75% EtOAc/hexanes, 10 min gradient; 75% EtOAc/hexanes, 10 min; 100 mL/min elution; 254 nm detection)