反应详情

温度

-30 °C

Treat a −78° C. solution of diisopropylamine (35 g, 0.346 mol) in THF (300 mL), under N2, drop-wise with a solution of n-butyllithium (2.5 M, 127 mL, 0.317 mol), warm to −30° C. for 0.5 h, re-cool to −78° C. and treat drop-wise with a solution of isobutyronitrile (19.9 g, 0.288 mol) in THF (100 mL). Stir the mixture at −78° C. for 0.5 h, treat with a solution of benzyl (2-bromoethyl)carbamate (74 g, 0.288 mol) in THF (100 mL), stir at −78° C. for 1 h, then warm to RT and stir overnight. Treat the mixture with H2O, separate the layers, extract the aqueous layer with EtOAc, wash the combined organics with brine, dry over Na2SO4, concentrate to dryness and purify via silica gel chromatography (EtOAc/Petroleum ether) to afford the title compound (15 g, 21% yield). MS (m/z): 247.2 (M+1).

1. temperaturere-cool to −78° C.
2. additiontreat
3. stirringstir at −78° C. for 1 h
4. temperaturewarm to RT
5. stirringstir overnight
6. customseparate the layers
7. extractionextract the aqueous layer with EtOAc
8. washwash the combined organics with brine
9. dry with materialdry over Na2SO4
10. concentrationconcentrate to dryness
11. custompurify via silica gel chromatography (EtOAc/Petroleum ether)