copper acetylacetonate in tetrahydrofuran 18 h; Ambient temperature;

1: 91 percent / tetrahydrofuran / 1.) -5 deg C, 30 min, 2.) 25 deg C, 1 h 2: 48 percent / aq. (NH4)2Ce(NO3)6 / acetonitrile / 0.5 h / 0 - 3 °C 3: 15 percent / AgO / dioxane / 0.33 h / 25 °C View Scheme

in tetrahydrofuran 0.333333 h; Heating;

1: 53 percent / CuBr-Me2S; LiI; TMSCl / 4 h / -78 °C 2: 91 percent / LAH / diethyl ether / 2 h 3: 89 percent / PCC / CH2Cl2 / 2 h / 20 °C 4: 55 percent / tetrahydrofuran / 0.33 h / Heating View Scheme