1: 81 percent / tert-butyl hydroperoxide / 2-methyl-propan-2-ol; CHCl3 / 10 h 2: 31 percent / lithium (2-thienyl)cyanocuprate / tetrahydrofuran; petroleum ether / 0.5 h / -78 °C 3: 51 percent / Mg(turnings), MeOH / tetrahydrofuran / 4 h / Ambient temperature 4: 95 percent / MCPBA 5: 73 percent / LiBH4, borane-THF / tetrahydrofuran / 12 h / 0 °C 6: 82 percent / 80percent aqu. AcOH / 0.5 h / 50 °C View Scheme