反应详情

Sodium hydride (2.8 g., 50% w/w dispersion in mineral oil) was added over 15 minutes to an ice cooled solution of t-butyl ethyl 2-allylmalonate (13.4 g.) in dry DMF (120 ml.) under nitrogen. The mixture was stirred at room temperature for 45 minutes and cooled to 0° C. 2-Ethylbenzoyl chloride (10.1 g.) was added over 2 minutes and the mixture stirred at room temperature for 18 hours. The DMF was evaporated and the residue shaken with water (100 ml.) and ethyl acetate (200 ml.). The ethyl acetate phase was separated, washed with saturated brine, dried (MgSO4) and evaporated. The oil obtained (21.8 g.) was purified by flash column chromatography on silica (650 g.) using toluene as eluant to give t-butyl ethyl 2-allyl-2-(2-ethylbenzoyl)malonate (14.3 g.) as an oil; NMR: 1.25 (15H,m), 2.7 (2H,q), 2.9 (2H,d), 4.12 (2H,q), 5.31 (2H,m), 6.05 (1H,m) and 7.35 (4H,m) ppm.

1. temperaturecooled to 0° C
2. stirringthe mixture stirred at room temperature for 18 hours
3. customThe DMF was evaporated
4. stirringthe residue shaken with water (100 ml.) and ethyl acetate (200 ml.)
5. customThe ethyl acetate phase was separated
6. washwashed with saturated brine
7. dry with materialdried (MgSO4)
8. customevaporated
9. customThe oil obtained (21.8 g.)
10. customwas purified by flash column chromatography on silica (650 g.)