反应详情

温度

100 °C

At room temperature, 176 mg (0.35 mmol) of tert-butyl [(6-chloropyridin-3-yl)methyl][3-hydroxy-3-(5-oxo-3-pyrrolidin-1-yl-2,5-dihydrofuran-2-yl)propyl]carbamate (cf. V-2) are stirred in a mixture of 7 ml of dichloromethane and 3.5 ml of trifluoroacetic acid for one hour. After concentration under reduced pressure, 10.5 ml of acetic acid are added to the residue, and the mixture is stirred at 100° C. for two hours. After concentration under reduced pressure, the residue is purified by column chromatography on silica gel (silica gel 60, Merck, particle size: 0.04 to 0.063 mm) using the mobile phase mixture dichloromethane:methanol (99:1 to 80:20). This gives (a) 6 mg (6% of theory) of 4-[(6-chloropyridin-3-yl)methyl]-7-hydroxy-5,6,7,7a-tetrahydrofuro-[3,2-b]pyridin-2(4H)-one as a mixture of diastereomers and (b) 30 mg (32% of theory) of 4-[(6-chloropyridin-3-yl)methyl]-5,6-dihydrofuro[3,2-b]pyridin-2(4H)-one.

1. concentrationAfter concentration under reduced pressure, 10.5 ml of acetic acid
2. additionare added to the residue
3. concentrationAfter concentration under reduced pressure
4. customthe residue is purified by column chromatography on silica gel (silica gel 60, Merck, particle size: 0.04 to 0.063 mm)