反应详情

Into a 200 ml four-necked flask, copper(II) acetate monohydrate (0.16 g) was added and dissolved in 5 ml of acetic acid. Zinc powder (2.8 g) was added to this solution, and after allowing the mixture to stir for 90 seconds, decantation was carried out. Acetic acid (1 ml) was added to the residue and decantation was repeated five times. Dry diethyl ether (6 ml) was added to the residue and decantation was repeated three times. The atmosphere in the reaction vessel was completely replaced with argon gas by operating a three-way stopcock that was connected to an aspirator. Allyl benzyl ether 6.3 g (6.3 ml, 40.5 mmol) dissolved in 60 ml of dry diethyl ether was placed in this reaction vessel. Trichloroacetyl chloride 5.0 ml (45 mmol) and phosphoryl trichloride 4.1 ml (45 mmol) that were dissolved in 40 ml of dry diethyl ether were added dropwise to the above solution over a period of one hour. This reaction solution was refluxed and stirred for 21 hours. After the reaction solution was returned to room temperature, it was filtered. The filtrate was quenched by the addition of water and washed with water and brine. The organic layer was dehydrated over anhydrous sodium sulfate and then concentrated. Acetic acid (33 ml) and zinc powder (13.3 g) were added to the residue, and the mixture was stirred under reflux for 4 hours. This reaction solution was filtered and the filtrate was concentrated. This residue was dissolved in ethyl acetate, and zinc powder precipitated upon neutralization with a saturated NaHCO3 solution was separated by filtration using Celite. The filtrate was separated into two layers and washed with a saturated NaHCO3 solution and brine. The organic layer was dehydrated over sodium sulfate and then concentrated. The unreacted allyl benzyl ether was removed by evaporation under reduced pressure in a glass tube oven. The residue was purified by silica gel chromatography (toluene:ethyl acetate=96:4) to obtain 3-(benzyloxymethyl)cyclobutanone (2.41 g, 29%) as a clear oil. A clear oil: b.p. 115° C./1.0 mmHg. (TLC; Rf=0.20 (G):(M))

1. customwas placed in this reaction vessel
2. additionwere added dropwise to the above solution over a period of one hour
3. temperatureThis reaction solution was refluxed
4. stirringstirred for 21 hours
5. customwas returned to room temperature
6. filtrationit was filtered
7. customThe filtrate was quenched by the addition of water
8. washwashed with water and brine
9. concentrationconcentrated
10. additionAcetic acid (33 ml) and zinc powder (13.3 g) were added to the residue
11. stirringthe mixture was stirred
12. temperatureunder reflux for 4 hours
13. filtrationThis reaction solution was filtered
14. concentrationthe filtrate was concentrated
15. dissolutionThis residue was dissolved in ethyl acetate
16. customzinc powder precipitated upon neutralization with a saturated NaHCO3 solution
17. customwas separated by filtration
18. customThe filtrate was separated into two layers
19. washwashed with a saturated NaHCO3 solution and brine
20. concentrationconcentrated
21. customThe unreacted allyl benzyl ether was removed by evaporation under reduced pressure in a glass tube oven
22. customThe residue was purified by silica gel chromatography (toluene:ethyl acetate=96:4)