1: 96 percent / PPTS / CH2Cl2 / 20 °C 2: 98 percent / TBAF / tetrahydrofuran / 2 h / 20 °C 3: 100 percent / DEAD; PPh3 / tetrahydrofuran / 20 °C 4: 96 percent / PPTS / ethanol / 4 h / 55 - 60 °C 5: 90 percent / Et3N; 4-(1-pyrrolidinyl)pyridine / 20 °C 6: Ph3SnH; AIBN / benzene / 2 h / Heating View Scheme

1: 96 percent / PPTs / CH2Cl2 / 20 °C 2: 98 percent / TBAF / tetrahydrofuran / 2 h / 20 °C 3: 100 percent / DEAD; PPh3 / tetrahydrofuran / 24 h / 20 °C 4: 96 percent / PPTs / ethanol / 4 h / 55 - 60 °C 5: 52 percent / DMAP / CH2Cl2 / 24 h / 20 °C 6: 60 percent / Ph3SnH; AIBN / benzene; acetonitrile / 2 h / Heating View Scheme