1: 51 percent / Mg(turnings), MeOH / tetrahydrofuran / 4 h / Ambient temperature 2: 95 percent / MCPBA 3: 73 percent / LiBH4, borane-THF / tetrahydrofuran / 12 h / 0 °C 4: 82 percent / 80percent aqu. AcOH / 0.5 h / 50 °C View Scheme