1: potassium tert-butylate / tetrahydrofuran / 72 h / 66 °C 2: diisobutylaluminium hydride; sodium tetrahydroborate; isopropyl alcohol / toluene / -78 - 20 °C 3: anhydrous iron chloride / 1,2-dichloro-ethane / 25 °C View Scheme

1: potassium tert-butylate / tetrahydrofuran / 72 h / 66 °C 2: potassium hydroxide / ethylene glycol / 12 h / 150 °C 3: Amberlyst-15 / toluene / 110 °C View Scheme