CC1(C)[C@H]2CC[C@]1(CS(O)(=O)=O)C(=O)C2.[Br:16][C:17]1[CH:18]=[C:19]2[C:23](=[CH:24][CH:25]=1)[CH2:22][C@H:21]([NH2:26])[CH2:20]2.C(=O)([O-])[O-].[K+].[K+].Cl[C:34]([O:36][CH2:37][C:38]1[CH:43]=[CH:42][CH:41]=[CH:40][CH:39]=1)=[O:35]>CCOC(C)=O.O>[Br:16][C:17]1[CH:18]=[C:19]2[C:23](=[CH:24][CH:25]=1)[CH2:22][C@H:21]([NH:26][C:34](=[O:35])[O:36][CH2:37][C:38]1[CH:43]=[CH:42][CH:41]=[CH:40][CH:39]=1)[CH2:20]2(S)-5-bromo-2,3-dihydro-1H-inden-2-amine((1R,4S)-7,7-dimethyl-2-oxobicyclo[2.2.1]heptan-1-yl)methanesulfonate (18.47 mmol, 8.21 g) was dissolved in EtOAc (30 mL)/water (30 mL) and potassium carbonate (55.4 mmol, 7.66 g) added. The mixture was cooled in an ice bath and benzyl chloroformate (20.32 mmol, 2.89 mL, 3.47 g) added dropwise. Stirring was continued overnight during which time the reaction came to room temperature. The crude reaction mixture was diluted with water and ethylacetate and the phases mixed and separated. The aqueous layer was further extracted with EtOAc (×2). Combined organics were dried and concentrated to give (S)-benzyl 5-bromo-2,3-dihydro-1H-inden-2-ylcarbamate as a colourless solid (6.89 g, 108%). 1H NMR (400 MHz, CDCl3) δ 2.79 (m, 2H) 3.26 (m, 2H) 4.53 (bm, 1H) 4.93 (bm, 1H) 5.10 (bs, 2H) 7.07 (m, 1H) 7.26-7.37 (m, 7H)
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