反应详情

To a stirred, cooled (0° C.) solution of (S)-4-hydroxymethyl-2,2-dimethyl-oxazolidine-3-carboxylic acid tert-butyl ester (1.36 g), 2-mercaptobenzothiazole (1.48 g) and triphenylphosphine (2.32 g) in THF (80 ml) under an argon atmosphere was added diethyl azodicarboxylate (4.1 ml; 40% solution in toluene). The mixture (soon turning to a yellow suspension, slowly warming up to r.t.) was stirred for 18 h overnight, then diluted with EtOAc and washed with sat. aq. Na2CO3. The aqueous phase was back extracted with EtOAc. The combined organics were washed with brine, dried over MgSO4, filtered and concentrated. The crude product was purified by column chromatography (SiO2; gradient: cyclohexane ->cyclohexane/EtOAc 85:15) to give (R)-4-(benzothiazol-2-ylsulfanyl-methyl)-2,2-dimethyl-oxazolidine-3-carboxylic acid tert-butyl ester (2.1 g) as light yellow viscous oil.

1. washwashed with sat. aq. Na2CO3
2. extractionThe aqueous phase was back extracted with EtOAc
3. washThe combined organics were washed with brine
4. dry with materialdried over MgSO4
5. filtrationfiltered
6. concentrationconcentrated
7. customThe crude product was purified by column chromatography (SiO2; gradient: cyclohexane ->cyclohexane/EtOAc 85:15)