反应详情

2.95 liters of methanol and 9.7 ml of conc. sulfuric acid are initially charged, and 175.0 g (1.21 mol) of cis-4-hydroxycyclohexanecarboxylic acid are added a little at a time at RT. The mixture is stirred at RT for 16 h. Almost all of the solvent is then removed on a rotary evaporator and the residue is taken up in 2 liters of a 1:1 mixture of saturated aqueous sodium bicarbonate solution and ethyl acetate. The phases are separated, and the organic phase is washed with 1 liter of 10% strength aqueous ammonium chloride solution and then dried over magnesium sulfate. After removal of the solvent on a rotary evaporator the residue is purified chromatographically on silica gel 60 (mobile phase: gradient ethyl acetate/petroleum ether 3:7→1:1).

1. customAlmost all of the solvent is then removed on a rotary evaporator
2. additionthe residue is taken up in 2 liters of a 1:1 mixture of saturated aqueous sodium bicarbonate solution and ethyl acetate
3. customThe phases are separated
4. washthe organic phase is washed with 1 liter of 10% strength aqueous ammonium chloride solution
5. dry with materialdried over magnesium sulfate
6. customAfter removal of the solvent
7. customon a rotary evaporator the residue
8. customis purified chromatographically on silica gel 60 (mobile phase: gradient ethyl acetate/petroleum ether 3:7→1:1)