1: SeO2 2: (i) MeLi, Et2O, HMPT, (ii) TsCl, (iii) LiCl 3: (i) nBuLi, (ii) /BRN= 2461289/ 4: Li, EtNH2 / tetrahydrofuran / -78 °C View Scheme

lithium; ethylenediamine in tetrahydrofuran T=-10°C; 3.33333 h;

(i) O3, Py, CH2Cl2, (ii) Me2S; Multistep reaction;

hydrogen; palladium on activated charcoal in methanol T=20°C; Catalytic hydrogenation; 24 h;

1: 69 percent / 3-chloro peroxybenzoic acid / CH2Cl2 / 1 h / 0 °C 2: 93 percent / aluminium isopropoxide / toluene / 8 h / Heating 3: 78 percent / t-BuOOH / 2.) VO(acac)2 / benzene / 4 h / Ambient temperature 4: 63 percent / copper(I) iodide / diethyl ether / 4 h / 0 °C 5: 1.) N,N-dimethylformamide dimethyl acetale / 1.) rt., overnight; 2.) acetic anhydride, boiling, 8 h 6: 84 percent / LiNH2 / liquid ammonia; hexane / 0.5 h View Scheme

sodium hydride

sodium hydride 1.) dioxane, reflux, 1 h; 2.) dioxane, reflux, 1 h; Yield given. Multistep reaction;

3: KN(SiMe3)2 / toluene / -78 °C 4: DIBAL / toluene / -78 °C 5: H2O, SiO2 6: 95 percent / NaBH4 / methanol 7: 74 percent / Li, EtNH2 / -78 °C View Scheme