1: PPh3 / CH2Cl2 2: 1) BuLi, 2) aq. HCl / 1) THF, -78 deg C, 2) EtOH 3: (COCl)2, DMSO View Scheme

1.1: BuLi / diethyl ether; hexane / 0.5 h / 20 °C 1.2: diethyl ether; hexane / 16 h / 20 °C 2.1: p-TsOH / dioxane; H2O / 2 h / 50 °C 3.1: imidazole / dimethylformamide / 2 h / 20 °C 4.1: N,N-diisopropylamine; n-BuLi / tetrahydrofuran; hexane / 0.5 h / 0 °C 4.2: tetrahydrofuran; hexane / 16 h / 20 °C 5.1: 70 percent / tetrabutylammonium fluoride / tetrahydrofuran / 4 h / 20 °C 6.1: 60 percent / Ph3P; imidazole; iodine / tetrahydrofuran / 2 h / 20 °C View Scheme