Scheme 3.

(a) (i) PhSO₂Cl, NEt₃, DMF, 0 °C; (ii) DIAD, PBu₃, THF, 0 °C; (b) (i) (R)-2-aminopent-4-en-1-ol, THF, 45 °C; (ii) Boc₂O, NEt₃, CH₃CN, 45 °C; (c) DIAD, PBu₃, THF, RT; (d) Mg, MeOH, sonication, RT; (e) 2-chloroethanesulfonyl chloride, NEt₃, CH₂Cl₂, RT; (f) Zhan Catalyst-1B, 1,2-DCE, 50 °C; (g) Pearlman’s catalyst, H₂ balloon, EtOAc, RT; (h) Dess–Martin periodinane, CH₂Cl₂, RT; (i) PPh₃, CBr₄, CH₂Cl₂, RT; (j) EtMgBr, THF, 0 °C; (k) 3-fluoro-2-iodoaniline, (PPh₃)₂PdCl₂, CuI, NEt₃, CH₃CN, 70 °C; (l) Pearlman’s catalyst, H₂ balloon, EtOH, RT; (m) (i) 3,3-Bis(4-fluorophenyl)propanoic acid, T3P, Hunig’s base, EtOAc, RT; (ii) HCl, dioxane, RT.