반응 #160810

반응 방정식

5-bromo-1-pentene

Cyclohexylamine

pyran-3-one

BuLi

→

title compound

4-(pent-4-en-1-yl)dihydro-2H-pyran-3(4H)-one

용매

benzene

THF

반응 조건

후처리

1. 1
   온도refluxed for 2 hr with a dean-stark trap
2. 2
   workup.DISTILLATIONThe benzene was then distilled off
3. 3
   workup.DISSOLUTIONthe residue was redissolved in THF (2 mL)
4. 4
   workup.ADDITIONwas added
5. 5
   workup.STIRRINGThe reaction mixture was stirred at 0° C. for 2 hr
6. 6
   온도The mixture was cooled
7. 7
   기타quenched with water
8. 8
   추출The reaction mixture was extracted with diethyl ether (3×20 mL)
9. 9
   세척The combined organic fractions were washed with water and brine (saturated, 100 mL)
10. 10
    기타dried
11. 11
    여과filtered
12. 12
    기타the solvent was evaporated under reduced pressure (400 mmhg)
13. 13
    기타The residue was purified by column chromatography on silica gel

실험 절차

Cyclohexylamine (3.43 ml, 30.0 mmol) was added to pyran-3-one (3000 mg, 30.0 mmol) in benzene (20 mL). The reaction mixture was stirred at RT for 30 min and then refluxed for 2 hr with a dean-stark trap. The benzene was then distilled off and the residue was redissolved in THF (2 mL) and added to BuLi (13.18 ml, 33.0 mmol) in THF (Volume: 30.000 ml) at 0° C. The reaction mixture was stirred at 0° C. for 1 h before 5-bromo-1-pentene (5582 mg, 37.5 mmol) was added. The reaction mixture was stirred at 0° C. for 2 hr. The mixture was cooled and quenched with water. The reaction mixture was extracted with diethyl ether (3×20 mL). The combined organic fractions were washed with water and brine (saturated, 100 mL), dried, filtered and the solvent was evaporated under reduced pressure (400 mmhg). The residue was purified by column chromatography on silica gel to provide the title compound. 1H NMR (500 MHz, CDCl3) δ 5.74-5.86 (m, 1H), 4.92-5.06 (m, 2H), 3.90-4.06 (m, 3H), 3.77-3.85 (m, 1H), 2.41-2.49 (m, 1H), 2.16-2.24 (m, 1H), 2.01-2.12 (m, 2H), 1.72-1.97 (m, 2H), 1.31-1.49 (m, 3H).

출처