تفاعل #53813

معادلة التفاعل

trans-(4-Hydroxy-cyclohexyl)-methyl-carbamic acid tert-butyl ester

1,4-Dibromobutane

NaOH

→

trans-[4-(4-Bromo-butoxy)-cyclohexyl]-methyl-carbamic acid tert-butyl ester

المردود 76.0%

المذيبات

CH2Cl2

ظروف التفاعل

المعالجة

1. 1
   workup.ADDITIONwere added
2. 2
   أخرىthe layers were separated
3. 3
   استخلاصThe inorganic layer was extracted with CH2Cl2
4. 4
   غسيلthe combined organic layers washed with brine
5. 5
   تجفيفdried over Na2SO4
6. 6
   أخرىThe excess of dibromide was removed in vacuo
7. 7
   أخرىthe residue was purified by column chromatography on silica gel with hexane:EtOAc 4:1 as eluent

الإجراء التجريبي

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).

المصدر