1: 99.5 percent / imidazole; Et3N / dimethylformamide / 1.33 h / 0 - 20 °C 2: 89 percent / NaI; pyridine / dimethylformamide / 2.5 h / 75 - 80 °C 3: 99 percent / LiOH*H2O / methanol; H2O / 8 h View Scheme

1.1: 89 percent / ethanol; H2O / 12 h / 20 °C 2.1: Zn / tetrahydrofuran / 0.17 h / 50 °C / ultrasonic irradiation 2.2: 69 percent / tetrahydrofuran / 5.5 h / 50 °C / ultrasonic irradiation 3.1: 84 percent / p-toluenesulfonic acid / CH2Cl2 / 2 h / 20 °C View Scheme

1.1: 89 percent / ethanol; H2O / 12 h / 20 °C 2.1: Zn / tetrahydrofuran / 0.17 h / 50 °C / ultrasonic irradiation 2.2: 69 percent / tetrahydrofuran / 5.5 h / 50 °C / ultrasonic irradiation 3.1: 84 percent / p-toluenesulfonic acid / CH2Cl2 / 2 h / 20 °C 4.1: 86 percent / K2CO3 / acetone / 20 h / 20 °C View Scheme