反应详情

To 2.93 g of 3 was added 5 mL of nitroethane with stirring. Approximately 5-6 g of Amberlyst A-21 was added, and the mixture was stirred at room temperature overnight. The mixture was filtered and the ion exchange resin was rinsed four times with 25 mL of dichloromethane. The filtrate was dried over anhydrous MgSO4, and the solvent was removed by rotary evaporation, which afforded 3.53 g (90%) of a mixture of stereoisomers of the desired nitro alcohol 4. 1H NMR δ (ppm) 5.2 (t, CH3C(CH3)═CH and CH2C(CH3)═CH), 4.4 (m, CHNO2), 2.2 (br s, CHOH), 2.0 (m, C═CHCH2CH2C(CH3)═CHCH2), 1.6-1.7 (all s, CH3C(CH3)═CHCH2CH2CCH3), 1.5 (d, CH3CHNO2), 1.2-1.5 (m, CH2CH(CH3)CH2), 0.9 (d, CH2CH(CH3)CH2).

1. additionApproximately 5-6 g of Amberlyst A-21 was added
2. stirringthe mixture was stirred at room temperature overnight
3. filtrationThe mixture was filtered
4. washthe ion exchange resin was rinsed four times with 25 mL of dichloromethane
5. dry with materialThe filtrate was dried over anhydrous MgSO4
6. customthe solvent was removed by rotary evaporation, which