반응 #55634

반응 방정식

Diborane

3-methyl-4-(tetrahydropyran-2-yloxy)-1-butene

bromine

sodium methoxide

→

1-bromo-3-methyl-4-(tetrahydropyran-2-yloxy)-butane

용매

water

tetrahydrofuran

tetrahydrofuran

methanol

반응 조건

후처리

1. 1
   workup.ADDITIONAfter the addition
2. 2
   온도The reaction mixture is cooled to 0°
3. 3
   workup.ADDITIONAfter the addition
4. 4
   온도to warm to room temperature
5. 5
   workup.STIRRINGstirred for 30 minutes
6. 6
   추출extracted with petroleum ether (2×200 ml)
7. 7
   세척The organic layer is washed with 5% sodium bicarbonate (100 ml), water (2×100 ml)
8. 8
   건조dried (Na2SO4)
9. 9
   기타The solvent is removed in vacuo
10. 10
    기타to give a colorless liquid
11. 11
    기타This crude product is purified by column chromatography in silica gel (500 g, 1% ether in petroleum ether)

실험 절차

Diborane in tetrahydrofuran (125 ml, 0.150 m) at 0° C. under nitrogen is added to a mixture of 3-methyl-4-(tetrahydropyran-2-yloxy)-1-butene (72 g, 0.423 m) and tetrahydrofuran (150 ml). After the addition is complete, the mixture is allowed to warm to room temperature and then stirred for 1 hour. The reaction mixture is cooled to 0° and bromine (24 ml, 0.43 mmole) and sodium methoxide (0.565 m) in methanol (300 ml) are added slowly simultaneously. After the addition is complete, the mixture is allowed to warm to room temperature and stirred for 30 minutes. The mixture is then treated with water (100 ml) and extracted with petroleum ether (2×200 ml). The organic layer is washed with 5% sodium bicarbonate (100 ml), water (2×100 ml) and dried (Na2SO4). The solvent is removed in vacuo to give a colorless liquid. This crude product is purified by column chromatography in silica gel (500 g, 1% ether in petroleum ether) to give 1-bromo-3-methyl-4-(tetrahydropyran-2-yloxy)-butane (71 g, 65%) as a colorless liquid.

출처