1: 92 percent / Pd(OAc)2, (Tol)3P, Et3N / acetonitrile / Heating 2: 98 percent / Zn, AcOH 3: 96 percent / pyridine / CH2Cl2 4: 92 percent / triphosgene, Et3N / CH2Cl2 5: 1.) Bu3SnH, AIBN; 2.) dil. HCl / 1.) MeCN, reflux; 2.) 0 deg C 6: NaOH / H2O; tetrahydrofuran 7: H2 / Pd-C / methanol View Scheme

1: 92 percent / Pd(OAc)2, (Tol)3P, Et3N / acetonitrile / Heating 2: 98 percent / Zn, AcOH 3: 96 percent / pyridine / CH2Cl2 4: 92 percent / triphosgene, Et3N / CH2Cl2 5: 1.) Bu3SnH, AIBN; 2.) dil. HCl / 1.) MeCN, reflux; 2.) 0 deg C 6: NaOH / H2O; tetrahydrofuran View Scheme

1: 91 percent / H2NNH2; FeCl3*H2O; activated charcoal / methanol / 38 h / Heating 2: LiCl; PPh3; K2CO3 / Pd(OAc)2 / dimethylformamide / 2 h / 80 °C 3: AcCl / methanol / 0.25 h / 0 °C View Scheme

1: 92 percent / Pd(OAc)2, (Tol)3P, Et3N / acetonitrile / Heating 2: 98 percent / Zn, AcOH 3: 96 percent / pyridine / CH2Cl2 4: 92 percent / triphosgene, Et3N / CH2Cl2 5: 1.) Bu3SnH, AIBN; 2.) dil. HCl / 1.) MeCN, reflux; 2.) 0 deg C 6: NaOH / H2O; tetrahydrofuran 7: H2 / Pd-C / methanol 8: DIBAL / CH2Cl2 / -78 °C 9: pyridine / CH2Cl2 / 0 °C 10: NaN3 / dimethylformamide 11: H2 / 10percent Pd-C / methanol View Scheme