1: 95 percent / acetonitrile / 1.) reflux, 3 h, 2.) r.t., overnight 2: DCC, DMAP / CH2Cl2 / Ambient temperature 3: Et3N / dioxane / 12 h / Heating 4: 92 percent / KOH / ethanol / 2 h / Heating 5: 93 percent / imidazole / dimethylformamide / 24 h / Ambient temperature 7: Ph2PLi / tetrahydrofuran; hexane / 16 h / Heating 8: Bu4NF / tetrahydrofuran / Ambient temperature View Scheme

1: 79 percent / imidazole / dimethylformamide / 24 h / Ambient temperature View Scheme

1: 1.) n-BuLi / 1.) hexane, ether, room temperature, overnight, 2.) xylene, 70-80 deg C, 3 h 2: oxalic acid / methanol; H2O / 2 h View Scheme

1: 1.) n-BuLi / 1.) hexane, ether, room temperature, overnight, 2.) xylene, 70-80 deg C, 3 h 2: oxalic acid / methanol; H2O / 2 h View Scheme

View Scheme

Yield given. Multistep reaction;