1: 87 percent / pyridine 2: 88 percent / trifluoroacetic acid, water / 1 h / Ambient temperature 3: p-toluenesulfonic acid monohydrate / benzene / 1 h / Ambient temperature 4: 1.41 g / 80percent acetic acid / 0.25 h / Ambient temperature 5: 76 percent / mercuric bromide, mercuric cyanide, molecular sieves 4A / acetonitrile / Ambient temperature 6: 82 percent / NaOMe / methanol / 1 h View Scheme

1: 87 percent / pyridine 2: 88 percent / trifluoroacetic acid, water / 1 h / Ambient temperature 3: p-toluenesulfonic acid monohydrate / benzene / 1 h / Ambient temperature 4: 1.41 g / 80percent acetic acid / 0.25 h / Ambient temperature 5: 76 percent / mercuric bromide, mercuric cyanide, molecular sieves 4A / acetonitrile / Ambient temperature 6: 82 percent / NaOMe / methanol / 1 h View Scheme