To a solution of 0.30 g (2.2 mmoles) of (S)-(4,5,6,7-tetrahydro-1H-indazol-5-yl)amine in 15 mL of ACN at 43° C., add 0.732 g (2.05 mmoles) of (R)-3-(3,5-Dichloro-4′-fluoro-biphenyl-4-ylmethyl)-5-hydroxy-dihydro-furan-2-one. Heat the mixture at 50° C. for 0.5 h and allow to cool to room temperature. Add 0.70 g (3.3 mmoles) of sodium triacetoxyborohydride. After 2.5 h, add an additional charge of sodium triacetoxyborohydride (100 mg). After 1 h, heat to 50° C. and add 15 mL of water slowly. Allow to cool to room temperature and stir the slurry overnight. Collect the solids by filtration and rinse with water (2×5 mL). Stir the wet cake with 15 mL of acetonitrile and filter. Rinse the cake with acetonitrile (2×5 mL) and dry in a vacuum oven to afford 0.65 g (62%) of the title compound as a solid. MS (m/z): 476 (M+1, 35Cl), 478 (M+1, 37Cl).
