[Sn](Cl)(Cl)(Cl)Cl.[Cl:6][C:7]1[CH:8]=[CH:9][C:10]([N+:18]([O-])=O)=[C:11]([N:13]2[CH2:17][CH2:16][CH2:15][CH2:14]2)[CH:12]=1.[NH4+].[OH-]>CCO>[NH2:18][C:10]1[CH:9]=[CH:8][C:7]([Cl:6])=[CH:12][C:11]=1[N:13]1[CH2:17][CH2:16][CH2:15][CH2:14]1Add pyrrolidine (0.97 g, 13.67 mmol) to a solution of 4-chloro-2-fluoro-1-nitrobenzene (2 g, 11.40 mmol) in 8 mL anhydrous DMSO under N2. Stir the reaction mixture at 80° C. for 1 h. Cool the mixture, pour into ice-H2O and extract with Et2O (3×30 mL). Wash the organic phase with water and brine, dry over MgSO4, filter, and concentrate. Chromatograph the residue on silica gel using hex/EtOAc 9:1 as eluent to afford 2.29 g (89%) of 1-(5-chloro-2-nitro-phenyl)-pyrrolidine as a yellow solid. Add tin chloride (10 g, 44.15 mmol) to a solution of 1-(5-chloro-2-nitrophenyl)pyrrolidine (2 g, 8.83 mmol) in 25 mL of EtOH under nitrogen. Heat the reaction mixture at 70° C. for 3 h. After cooling, pour the mixture into ice-water, basify (pH=9) with NH4OH, and extract with EtOAc (3×100 mL). Dry the organic phase over MgSO4, concentrate, and purify the residue by silica gel chromatography using hex/EtOAc 8:2 as eluent to obtain 1.56 g (88%) of 1-(2-amino-5-chlorophenyl)pyrrolidine as an oil.
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