1: 89 percent / B2H6 / tetrahydrofuran / 8 h / ice cooling 2: 80 percent / 1percent HCl / tetrahydrofuran / 1 h / Heating 3: 93 percent / Jones reagent / acetone / 2 h / ice cooling 4: 87 percent / anhyd. K2CO3 / ethanol / 2.5 h / Heating 5: 37 percent / LiAlH4 / diethyl ether / 1.) r.t., 5 h, 2.) reflux, 4 h View Scheme