1: 92 percent / NH4HCO2 / Pd(OH)2-C / H2O; methanol / 1.5 h / Heating 2: pyridine / 48 h / 5 °C 3: 59.4 mg / TMSCl / pyridine 4: 25.8 mg / pyridine; H2O / 19 h / 20 °C 5: 62 percent / DCC; N-hydroxysuccinimide / dimethylformamide / 0 - 20 °C 6: 36 percent / TFA / 0.13 h / 20 °C View Scheme

1: 92 percent / NH4HCO2 / Pd(OH)2-C / H2O; methanol / 1.5 h / Heating 2: pyridine / 48 h / 5 °C 3: 59.4 mg / TMSCl / pyridine 4: 25.8 mg / pyridine; H2O / 19 h / 20 °C View Scheme

hydrogen; palladium on activated charcoal in ethanol Ambient temperaturefurther catalyst and solvent;

With  sodium hydroxide; water in  tetrahydrofuran T=20°C; 48 h;   

Multi-step reaction with 6 steps 1: 100 percent / pyridine / 12 h / 20 °C2: 95 percent / Me2BBr; Et3N / CH2Cl2 / 1 h / -78 °C3: 89 percent / Et3N / tetrahydrofuran; acetonitrile / 48 h / 20 °C4: NaH / tetrahydrofuran / 12 h / -20 °C5: 112 mg / TBAF / tetrahydrofuran / 1 h / 20 °C6: 92 percent / NaOH; H2O / tetrahydrofuran / 48 h / 20 °C