1.1: LDA / tetrahydrofuran; hexane / 0.75 h / -78 °C 1.2: 90 percent / tetrahydrofuran; hexane / 1 h 2.1: 94 percent / PPTS / benzene / 1.5 h / Heating 3.1: LiAlH4 / tetrahydrofuran / 0.17 h / 0 °C 3.2: 76 percent / aq. HCl / tetrahydrofuran / 0.5 h / 20 °C 4.1: BF3*Et2O; ethylene glycol / CH2Cl2 / 20 °C 4.2: 75 percent / aq. HCl / tetrahydrofuran / 24 h View Scheme