1: diethyl ether 2: aq.-ethanolic KOH View Scheme

1: 74.2 percent / chromic acid / tetrahydrofuran / 0.17 h / 0 °C 2: 89.6 percent / NaOH (10percent) / methanol / 4 h / Ambient temperature View Scheme

1: n-BuLi / hexane; tetrahydrofuran / 18 h / Ambient temperature 2: 92 percent / K2Os2(OH)4, (DHQD)2PHAL, K2CO3, potassium ferricyanate, CH3SO2NH2 / H2O; 2-methyl-propan-2-ol / 96 h / Ambient temperature 3: 1) CH3SO2Cl, pyridine, 2) K2CO3 / 1) CH2Cl2, RT, 2) aq. CH3OH, RT, 18 h View Scheme