1: 1.) HN3, Ph3P, DEAD; 2.) PPh3, H2O / 1.) benzene, r.t.; 2.) THF, 55 deg C 2: 90 percent / DMAP / CH2Cl2 / 0 °C 3: 96 percent / SnCl4 / CH2Cl2 / Heating 4: 84 percent / AgOCOCF3 / Ambient temperature 5: 79 percent / CSA / toluene 6: 73 percent / LiOH, H2O / methanol / Ambient temperature 7: 95 percent Turnov. / di(2-pyridyl)thionocarbonate, DMAP / toluene / 73 °C 8: 100 percent / TFA, H2O / 0 °C View Scheme

1: 1.) HN3, Ph3P, DEAD; 2.) PPh3, H2O / 1.) benzene, r.t.; 2.) THF, 55 deg C 2: 90 percent / DMAP / CH2Cl2 / 0 °C 3: 96 percent / SnCl4 / CH2Cl2 / Heating 4: 84 percent / AgOCOCF3 / Ambient temperature View Scheme

1: 1.) HN3, Ph3P, DEAD; 2.) PPh3, H2O / 1.) benzene, r.t.; 2.) THF, 55 deg C 2: 90 percent / DMAP / CH2Cl2 / 0 °C 3: 96 percent / SnCl4 / CH2Cl2 / Heating 4: 84 percent / AgOCOCF3 / Ambient temperature 5: 89 percent / PPTS / toluene / 85 °C 6: 86 percent / LiOH, H2O / methanol / Ambient temperature View Scheme

1: 1.) HN3, Ph3P, DEAD; 2.) PPh3, H2O / 1.) benzene, r.t.; 2.) THF, 55 deg C 2: 90 percent / DMAP / CH2Cl2 / 0 °C 3: 78 percent / AgNO3, H2O / dioxane / Heating 4: di(2-pyridyl)thionocarbonate, DMAP / toluene / 73 °C 5: 76 percent / H2 / Pd(OH)2/C / ethanol / Ambient temperature View Scheme