[CH2:1]([N:8]([CH2:13]OC)[Si](C)(C)C)[C:2]1[CH:7]=[CH:6][CH:5]=[CH:4][CH:3]=1.[CH3:16][O:17][C:18](=[O:28])/[CH:19]=[CH:20]/[C:21]1[CH:26]=[CH:25][CH:24]=[C:23]([Br:27])[CH:22]=1.F[C:30](F)(F)C(O)=O>C(Cl)Cl.O>[CH3:16][O:17][C:18]([C@H:19]1[C@H:20]([C:21]2[CH:26]=[CH:25][CH:24]=[C:23]([Br:27])[CH:22]=2)[CH2:13][N:8]([CH2:1][C:2]2[CH:3]=[CH:4][CH:5]=[CH:6][CH:7]=2)[CH2:30]1)=[O:28]
Add benzyl-methoxymethyl-trimethylsilanyl-amine (14.7 g, 2.20 mmol) to a solution of trans-3-(3-bromo-phenyl)-acrylic acid methyl ester (10.0 g, 41.4 mmol) in methylene chloride (80 mL). Cool the mixture to 0° C. and stir for 10 min then add trifluoroacetic acid (0.92 mL, 12.4 mmol) and stir the mixture at 0° C. for an additional 4 h. Dilute the reaction mixture with water and extract with methylene chloride. Dry the combined organic phase over anhydrous sodium sulfate and concentrate under reduced pressure. Purify the residue by silica gel chromatography to provide 12 g (77%) of trans-1-benzyl-4-(3-bromo-phenyl)-pyrrolidine-3-carboxylic acid methyl ester.
Wird geladen…
