1: 61 percent / 2-methyl-propan-2-ol; CH2Cl2 / 1 h / 50 °C 2: 95 percent / Zn / acetic acid; tetrahydrofuran / 3 h / Ambient temperature 3: 94 percent / (COCl)2, DMSO, Et3N / CH2Cl2 / -78 deg C then 0 deg C, 2 h 4: 88 percent / 1M NaBH3CN / methanol; tetrahydrofuran / 19 h / 0 - 7 °C 5: 89 percent / 1.) 20percent aq. HCl, anisole; 2.) 1N NaOH; 3.) Dowex 50Wx4 / 1.) THF, rt., 24 h; 2.) rt., 22 h; 3.) H2O then 15percent aq. NH3 View Scheme