1: 96 percent / tetrabutylammonium hydrogensulfate, NaOH / H2O; benzene / 24 h / 25 °C 2: 1.) SeO2, pyridine, 2.) NaOH / 1.) 95 deg C, 12 h, 2.) ethanol, water, reflux, 12 h 3: 1.2 g / H2SO4 / 3 h / 25 °C View Scheme

sulfuric acid Ambient temperature; Yield given;

2: 96 percent / tetrabutylammonium hydrogensulfate, NaOH / H2O; benzene / 24 h / 25 °C 3: 1.) SeO2, pyridine, 2.) NaOH / 1.) 95 deg C, 12 h, 2.) ethanol, water, reflux, 12 h 4: 1.2 g / H2SO4 / 3 h / 25 °C View Scheme

PdCl2(tpp)2; diisobutylaluminium hydride; toluene-4-sulfonic acid 1.) THF, reflux, 2.) EtOH, reflux; Yield given. Multistep reaction;

Yield given. Multistep reaction. Yields of byproduct given;