반응 #445826

반응 방정식

Benzenesulphonamide

sodium methoxide

dimethyl formamide

ethyl 5-bromo-3,3-dimethyl-pentanoate

→

Ethyl 3,3-dimethyl-5-(benzenesulphonamido)pentanoate

용매

methanol

water

반응 조건

후처리

1. 1
   기타The clear solution was evaporated to dryness
2. 2
   추출the mixture was extracted with ether
3. 3
   건조the ether phase, after being dried over sodium sulphate
4. 4
   기타was evaporated
5. 5
   workup.ADDITIONTreatment of the solid residue with a mixture of toluene and cyclohexane (9:1)
6. 6
   workup.WAITleft most of the unreacted benzenesulphonamide undissolved
7. 7
   여과After filtration
8. 8
   기타the solution was evaporated
9. 9
   기타the residue was purified by chromatography on silica gel with a mixture of methylene chloride and ethanol (98:2)

실험 절차

Benzenesulphonamide (9.6 g, 61.1 mmol) was added to a stirred solution of sodium methoxide (1.6 g, 29.6 mmol) in methanol (100 ml). The clear solution was evaporated to dryness, then dimethyl formamide (100 ml) and ethyl 5-bromo-3,3-dimethyl-pentanoate (7.0 g, 32.8 mmol) were added and the mixture was heated for eight hours at 70° C. The solution was then poured into water (600 ml), the mixture was extracted with ether and the ether phase, after being dried over sodium sulphate, was evaporated. Treatment of the solid residue with a mixture of toluene and cyclohexane (9:1) left most of the unreacted benzenesulphonamide undissolved. After filtration, the solution was evaporated and the residue was purified by chromatography on silica gel with a mixture of methylene chloride and ethanol (98:2). Yield: 4.6 g (50% of theory), oily substance, nD20 =1.5083.

출처