1: 96 percent / pyridine; 4-(dimethylamino)pyridine / 4 h 2: 56 percent / aq. NaOH; Bu4NHSO4 / CH2Cl2 / 120 h / Heating 3: 87 percent / TFA; Et3SiH / CH2Cl2; CHCl3 / 2 h 4: 90 percent / imidazole / dimethylformamide / 3 h / -35 - 20 °C 5: 80 percent / di-tert-butylmethylpyridine; DMTST; MS 4A / CH2Cl2 / 2 h / 20 °C 6: 100 percent / TAS-F / dimethylformamide / 1 h 7: 100 percent / H2; Amberlite IR-45(OH-) / Pd/C / methanol; ethyl acetate / 5688.78 Torr View Scheme