반응 #2146744
ord-c357324bc76149fb8030c029084899f2
반응 방정식
반응물
시약
반응 조건
후처리
- 1workup.STIRRINGstirred at −78° C. for about 2 h
- 2기타slowly brought to room temperature
- 3workup.STIRRINGstirred for 1 h
- 4기타The DCM layer is separated
- 5세척washed with 1 N HCl solution and saturated brine
- 6건조dried (anhyd Na2SO4)
- 7농축concentrated
- 8기타purified by flash chromatography (hexane:ethyl acetate=70:30)
실험 절차
To a cooled solution of oxalyl chloride (2.15 ml, 25.1 mmol, 1.3 equiv.) in DCM (20 ml) at −78° C. is added a solution of DMSO (2.85 ml, 36.5 mmol, 1.9 equiv.) in DCM (30 ml) and stirred at −78° C. for 30 mins. Then a solution of (3R,4S,5R)-5-(2,4-Dichlorobenzyloxymethyl)-4-(2,4-dichlorobenzyloxy)-2-methoxy-tetrahydrofuran-3-ol I-2 (9.6 g, 18.8 mmol, 1 equiv.) in DCM (50 ml) is added slowly and stirred at −78° C. for about 2 h. After that, triethylamine (15.8 ml, 114 mmol, 6.0 equiv.) is added to the reaction mixture and slowly brought to room temperature and stirred for 1 h. After the reaction is completed, the mixture is diluted with water (100 ml) and DCM (50 ml). The DCM layer is separated and washed with 1 N HCl solution and saturated brine, dried (anhyd Na2SO4), concentrated and purified by flash chromatography (hexane:ethyl acetate=70:30) to give (4R,5R)-5-(2,4-Dichlorobenzyloxymethyl)-4-(2,4-dichlorobenzyloxy)-2-methoxy-dihydrofuran-3-one I-3 as slightly yellow oil.