反应详情

温度

0 °C

Neat 4-methylmorpholine (2.7 mL, 24.6 mmol) was added, via syringe, to a rapidly stirred, 0° C., solution of 4-tert-butoxycarbonylamino-tetrahydro-pyran-4-carboxylic acid (5.0 g, 20.4 mmol) and isobutyl chloroformate (3.2 mL, 24.5 mmol) in anhydrous tetrahydrofuran (200 mL) contained in a 1000 mL round bottomed flask. Precipitate immediately formed. The suspension was allowed to stir at 0° C. under N2 blanket for 20 minutes then a hand swirled, gas evolving, suspension of sodium borohydride (2.3 g, 61.3 mmol) in methanol (65 mL) was added, at as fast of a rate as possible while maintaining control of the concomitant reaction foaming. When observable gas evolution had ceased the opaque white reaction suspension was transferred to a separatory funnel containing saturated aqueous sodium chloride (500 mL) and extracted with ethyl acetate. Combined organic extracts were dried (MgSO4), passed through a plug of silica gel, and evaporated to obtain 4.89 g of off white solid which was used without further purification. LRMS (ESI) m/z 232.2 [(M+H)+, calcd for C11H22NO4232.3].

1. customPrecipitate immediately formed
2. stirringto stir at 0° C. under N2 blanket for 20 minutes
3. additionwas added
4. temperatureat as fast of a rate as possible while maintaining control of the concomitant reaction foaming
5. customwas transferred to a separatory funnel
6. extractionextracted with ethyl acetate
7. dry with materialCombined organic extracts were dried (MgSO4)
8. customevaporated
9. customto obtain 4.89 g of off white solid which
10. customwas used without further purification