silica gel in toluene 9 h; Heating;

Multi-step reaction with 4 steps 1: 99 percent / p-toluenesulfonic acid hydrate / 60 h2: 99 percent / KOH / methanol / 0.5 h3: 88 percent / trifluoroacetic acid, 1,3-dicyclohexylcarbodiimide / benzene; pyridine; dimethylsulfoxide / 18 h4: 1.) n-BuLi, triphenylmethane / 1.) hexane-THF, 0 deg C, 15 min; 2.) hexane-THF, -78 deg C,15 min  

Multi-step reaction with 3 steps 1: 99 percent / KOH / methanol / 0.5 h2: 88 percent / trifluoroacetic acid, 1,3-dicyclohexylcarbodiimide / benzene; pyridine; dimethylsulfoxide / 18 h3: 1.) n-BuLi, triphenylmethane / 1.) hexane-THF, 0 deg C, 15 min; 2.) hexane-THF, -78 deg C,15 min