sulfuric acid in ethanol; water 0.25 h; Heating;

1: 1.) n-BuLi / 1.) THF, cyclohexane, -78 deg C, 5 min, 2.) -78 deg C, 5 min 2: 90 percent / H2SO4 / ethanol; H2O / 0.25 h / Heating View Scheme

1: 1.) n-BuLi / 1.) THF, cyclohexane, -78 deg C, 5 min, 2.) -78 deg C, 5 min 2: 90 percent / H2SO4 / ethanol; H2O / 0.25 h / Heating View Scheme

1.1: Cp2Zr(H)Cl / tetrahydrofuran / 20 °C 1.2: 60 percent / CuBr*Me2S / tetrahydrofuran / 4 h / 25 °C 2.1: MCPBA / CH2Cl2 / 20 °C 3.1: TFA / methanol / 2 h / Heating View Scheme