反应详情

To a suspension of 2.0 g (8.7 mmol) trans-(4-Hydroxy-cyclohexyl)-methyl-carbamic acid tert-butyl ester in 56.5 ml (261 mmol, 30 eq) 1,4-Dibromobutane, 0.89 g (2.6 mmol, 0.3 eq) tetrabutylammoniumhydrogensulfate and 56 ml 50% aqueous NaOH were added. The mixture was stirred at RT for 4 days, CH2Cl2 was added and the layers were separated. The inorganic layer was extracted with CH2Cl2, the combined organic layers washed with brine and dried over Na2SO4. The excess of dibromide was removed in vacuo and the residue was purified by column chromatography on silica gel with hexane:EtOAc 4:1 as eluent yielding 2.4 g (76%) trans-[4-(4-Bromo-butoxy)-cyclohexyl]-methyl-carbamic acid tert-butyl ester as light yellow oil, MS: 364 (MH+, 1Br).

1. additionwere added
2. customthe layers were separated
3. extractionThe inorganic layer was extracted with CH2Cl2
4. washthe combined organic layers washed with brine
5. dry with materialdried over Na2SO4
6. customThe excess of dibromide was removed in vacuo
7. customthe residue was purified by column chromatography on silica gel with hexane:EtOAc 4:1 as eluent