Reaction Steps
To a solution of 13 (0.699 g, 1.38 mmol) in 14 mL of a 1:1 solution of dry MeOH: CH2Cl2 under a N2 atmosphere was added sodium borohydride (NaBH4, 156 mg, 4.13 mmol). The reaction mixture was dried after 5 hours and the residue was loaded onto a silica column. The product was eluted with a 10% EtOAc-Hex to provide the product 20. 1H NMR (300 MHz, CDCl3) δ 1.10 (d, 9H, J=8 Hz), 1.16 (d, 9H, J=7 Hz), 1.52 (septet, 3H, J=8 Hz), 3.72 (d, 1H, J=11 Hz), 4.11 (s, 3H), 4.23 (d, 1H, J=15 Hz), 4.85 (d, 1H, J=15 Hz), 5.79 (d, 11H, J=11 Hz), 6.97 (t, 2H, J=9 Hz), 7.27 (dd, 2H, J=6, 9 Hz), 7.43 (dd, 1H, J=4, 8 Hz), 8.43 (dd, 1H, J=2, 8 Hz), 8.81 (dd, 1H, J=2,4 Hz); 13C NMR (75 MHz, CDCl3) δ 14.8. 18.2,41.3, 61.6, 78.6, 115.3, 115.6, 116.6, 122.3, 126.0, 126.8, 130.1, 130.2, 131.1, 132.8, 143.1, 143.8, 148.3, 162.1 (d, J=244 Hz), 165.2; EI MS (m/z) 511.5 [MH+], 533.4 [M+Na].
