1: 0.5 h / 160 °C 2: 1.) KOH, 2.) 2 N H2SO4 / methanol; H2O / 3 h / Heating View Scheme

1: 68 percent / conc. H2SO4 / 15 h 2: 73 percent / 2 N KOH aq. / methanol / 3.5 h / Heating View Scheme

1: 68 percent / conc. H2SO4 / 15 h 2: 73 percent / 2 N KOH aq. / methanol / 3.5 h / Heating 3: 68 percent / 0.17 h / 295 - 300 °C 4: 44 percent / finely divided nickel / xylene; H2O / 10 h / Heating View Scheme