1: 95 percent / pyridine / 0.17 h / Heating 2: 1.) SOCl2, 2.) NH3, methanol / 1.) reflux, 2 min, 2.) 20 deg C, 24 h View Scheme

Multi-step reaction with 7 steps 1: acetyl chloride, pyridine2: 16 percent / pyridine / 1,2-dichloro-ethane / -5 - 0 °C3: 97.6 percent / pyridine, Ac2O, CrO3 / CH2Cl2 / 0.08 h4: 31.2 percent / diethyl ether / 0.17 h / 0 °C5: 63 percent / N-methylimidazole / 0.5 h / 150 °C6: SnCl4 / 1,2-dichloro-ethane / 15 h / Heating7: 1.) CF3SO3SiMe3, 2.) NaOMe, MeOH / 1.) 1,2-dichloroethane, 15 min, reflux, 2.) 1,2-dichloroethane, 20 deg C, 1 h