1: acetic acid anhydride; pyridine View Scheme

1: 92 percent / pyridine / acetic anhydride / 3 h / Heating 2: 75 percent / aq. NaOH / benzene / 20 h / Ambient temperature 3: 80 percent / H2SO4 / 24 h / Heating 4: 70 percent / NaBH4 / methanol / 4 h / 0 °C 5: 60 percent / pyridine / 1.) 0 deg C, 1 h, 2.) room temperature, 3 h 6: LiI, HMPA / 150 °C View Scheme

pyridine in acetic anhydride 3 h; Heating;

1: 92 percent / pyridine / acetic anhydride / 3 h / Heating 2: 75 percent / aq. NaOH / benzene / 20 h / Ambient temperature View Scheme

1: 92 percent / pyridine / acetic anhydride / 3 h / Heating 2: 75 percent / aq. NaOH / benzene / 20 h / Ambient temperature 3: 80 percent / H2SO4 / 24 h / Heating View Scheme

1: PbO 2: benzyl-trimethyl-ammonium hydroxide View Scheme

1: PbO 2: benzyl-trimethyl-ammonium hydroxide 3: aqueous H2SO4 View Scheme

1: aqueous KOH-solution 2: Beim Erhitzen unter vermindertem Druck View Scheme