C[Si](C)(C)[C:3]1[S:4][CH:5]=[CH:6][N:7]=1.[CH2:10]([O:12][C:13](=[O:19])[CH2:14][CH2:15][C:16](Cl)=[O:17])[CH3:11].C([O-])(O)=O.[Na+]>C(Cl)Cl>[CH2:10]([O:12][C:13](=[O:19])[CH2:14][CH2:15][C:16](=[O:17])[C:3]1[S:4][CH:5]=[CH:6][N:7]=1)[CH3:11]To a stirred solution of 2-trimethylsilanyl-thiazole (2.6 g, 16.53 mmol) in DCM (30 mL) is added a solution of 3-chlorocarbonyl-propionic acid ethyl ester (5.4 g, 32.81 mmol)in DCM (10 mL). The mixture is stirred overnight at room temperature. To the mixture is added 5% NaHCO3 (30 mL) and mixture is stirred at room temperature for 20 minutes. The organic layer is separated and the aqueous lay is extracted with DCM (2×50 mL). The combined organic layers are dried and the solvent removed. The residue is separated by column (methylene chloride) to give 4-oxo-4-thiazol-2-yl-butyric acid ethyl ester.
Wird geladen…