反应详情

温度

-78 °C

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.

1. stirringstirred at −78° C. for about 2 h
2. customslowly brought to room temperature
3. stirringstirred for 1 h
4. customThe DCM layer is separated
5. washwashed with 1 N HCl solution and saturated brine
6. dry with materialdried (anhyd Na2SO4)
7. concentrationconcentrated
8. custompurified by flash chromatography (hexane:ethyl acetate=70:30)