Sodium borohydride → ((1R,3R)-1-amino-3-(4-bromophenyl)cyclopentyl)methanol
Reaction equation
[NH2:1][C@:2]1([C:14](OC)=[O:15])[CH2:6][CH2:5][C@@H:4]([C:7]2[CH:12]=[CH:11][C:10]([Br:13])=[CH:9][CH:8]=2)[CH2:3]1.[BH4-].[Na+]>CO>[NH2:1][C@:2]1([CH2:14][OH:15])[CH2:6][CH2:5][C@@H:4]([C:7]2[CH:12]=[CH:11][C:10]([Br:13])=[CH:9][CH:8]=2)[CH2:3]1Participants
4
Procedure
(1R,3R)-Methyl 1-amino-3-(4-bromophenyl)cyclopentanecarboxylate (1-2, 3.88 g, 13.01 mmol) was dissolved in MeOH (65.1 ml) and sodium borohydride (1.477 g, 39.0 mmol) was added portionwise. Additional sodium borohydride was added (0.5 equiv every 1 h) portionwise until the reaction was determined to be complete by HPLC analysis. The reaction was found to be complete after 2 hours. The reaction mixture was quenched with water and diluted with ethyl acetate. The aqueous layer was back extracted three times with EtOAc. The organic layers were combined, washed with saturated NaCl, dried over MgSO4, filtered and concentrated to afford ((1R,3R)-1-amino-3-(4-bromophenyl)cyclopentyl)methanol (3.19 g, 11.81 mmol). HPLC ret time=0.68 min; LC/MS M+1=272: 1H NMR (400 MHz, CDCl3) δ 7.42 (d, J=8.4 Hz, 2H), 7.13 (d, J=8.4 Hz, 2H), 3.49 (s, 2H), 3.32-3.41 (m, 1H), 2.19-2.25 (m, 1H), 1.98-2.07 (m, 1H), 1.90-1.95 (m, 1H), 1.66-1.74 (m, 2H), 1.52-1.60 (m, 1H).