1: sodium iodide / acetonitrile / 1 h / 23 °C 2: sodium thiosulfate / H2O View Scheme

1: 71 percent / 1,8-diazabicyclo[5.4.0]undec-7-ene / benzene / 12 h / 24 °C 2: 85 percent / aq. KOH / ethanol / 16 h / 24 °C 3: diethyl ether View Scheme

Yield given;