1: 90 percent / nBu4NF / tetrahydrofuran / 1 h / 25 °C 2: HS(CH2)3SH, Et3N / methanol / 24 h / 25 °C View Scheme

1: 91 percent / Ph3P, H2O, pyridine 2: 92 percent / NaHCO3 / dioxane; H2O 3: tetrazole / CH2Cl2; acetonitrile / 0.5 h 4: iodine, pyridine, water / CH2Cl2 5: 95 percent / 33percent HNMe2 / ethanol / 72 h / 45 °C 6: 75 percent / tetrabutylammonium fluoride / tetrahydrofuran / 72 h / 45 °C View Scheme

tetrabutyl ammonium fluoride in tetrahydrofuran T=25°C; 1 h;

1: 91 percent / triphenylphosphine, water / pyridine / 11 h / 55 - 60 °C 2: 92 percent / N-ethoxycarbonyl-2-ethoxy-1,2-dihydroquinoline / ethanol / 14 h / 50 °C 3: Et3N, DMAP / benzene / 6 h / Ambient temperature 4: benzene; acetonitrile / 48 h / 65 - 70 °C 5: 92 percent / tetra-butylammonium fluoride / tetrahydrofuran / 20 h / Ambient temperature View Scheme

With  pyridine; water; triphenylphosphine T=55 - 60°C; 11 h;   

Multi-step reaction with 2 steps 1: 91 percent / Ph3P, H2O, pyridine2: 92 percent / NaHCO3 / dioxane; H2O  

Multi-step reaction with 7 steps 1: 91 percent / PPh3 / H2O; pyridine2: 88 percent / NEt3 / tetrahydrofuran3: iPr2NH*tetrazole / CH2Cl2; acetonitrile / 0.5 h4: tetrazole5: I2 / H2O; pyridine; CH2Cl2 6: 33percent HNMe2 / ethanol / Ambient temperature7: 86 percent / 1.) tetrabutylammonium fluoride (TBAF); 2.) ion exchange resin (H+, OH-) / 1.) THF, 35 deg C