1: 94 percent / NIS; TMSOTf / CH2Cl2 / -15 - 20 °C 2: 92 percent / NaOMe / methanol / Heating 3: p-TsOH / dimethylformamide 4: 73 percent / DCC; DMAP / CH2Cl2 / 20 °C 5: 87 percent / NIS; TMSOTf / CH2Cl2 / -30 - 20 °C 6: 92 percent / HOAc / H2O / 3 h / 80 °C 7: 93 percent / imidazole; DMAP / dimethylformamide / 20 °C 8: 58 percent / BF3*Et2O / CH2Cl2 / -40 - 20 °C 9: 95 percent / CAN / CH2Cl2; methanol / 1 h / 20 °C 10: 81 percent / NaOMe / methanol / 20 °C View Scheme

chloramine-T in acetonitrile T=20°C; 2 h; Title compound not separated from byproducts;

1: in dichloromethane T=20°C; 1 h; Molecular sieveInert atmosphere; 2: With bromine in dichloromethane T=20°C; 0.0833333 h;

bromine in chloroform-d1 T=20°C; 16 h; Cooling with liquid nitrogen; optical yield given as percent destereoselective reaction;

1: 94 percent / NIS; TMSOTf / CH2Cl2 / -15 - 20 °C 2: 92 percent / NaOMe / methanol / Heating View Scheme

With  pyridine T=20°C; 16 h;