Dimethyl Sulfoxide → ethyl 3-{[(2R)-2-(4,5-diphenyloxazol-2-yl)-4-oxopyrrolidin-1-yl]methyl}phenoxyacetate

To a solution of oxalyl chloride (0.050 mL) in CH2Cl2 (10 mL) was added a solution of DMSO (0.061 mL) in CH2Cl2 (0.5 mL) keeping the temperature below −55° C., and stirred for 30 minutes. To the mixture was added a solution of ethyl 3-{[(2R, 4R)-2-(4,5-diphenyloxazol-2-yl)-4-hydroxypyrrolidin-1-yl]methyl}phenoxyacetate (238 mg) in CH2Cl2 (3 mL) at the same temperature, then stirred for 1 hour. To the reaction mixture was added triethylamine (0.27 mL), and warmed to room temperature over 30 minutes. After stirring at the same temperature for 30 minutes, the mixture was diluted with EtOAc, washed with water, saturated sodium hydrogen carbonate, water and brine, dried (MgSO4), evaporated. The residue was purified by silica gel column chromatography (hexane-EtOAc 2:1) to give ethyl 3-{[(2R)-2-(4,5-diphenyloxazol-2-yl)-4-oxopyrrolidin-1-yl]methyl}phenoxyacetate (191.8 mg).

1. customthe temperature below −55° C.
2. stirringstirred for 1 hour
3. stirringAfter stirring at the same temperature for 30 minutes
4. washwashed with water, saturated sodium hydrogen carbonate, water and brine
5. dry with materialdried (MgSO4)
6. customevaporated
7. customThe residue was purified by silica gel column chromatography (hexane-EtOAc 2:1)

ORD-Eintrag

ord-00216b76535542de86ed6ab32301df54

Quelldatensatz

uspto-grants-2003_12

DOI

10.6084/m9.figshare.5104873.v1

Patentnummer

US06660759B1