potassium hydroxide in tert-butyl alcohol T=70°C;

1.1: pyridine / tetrahydrofuran / 0.5 h / 20 °C 2.1: sec.-butyllithium / cyclohexane; tetrahydrofuran / 1.17 h / -78 °C 2.2: 0.58 h / -78 °C 3.1: triethylamine; copper(l) iodide / bis-triphenylphosphine-palladium(II) chloride / tetrahydrofuran / 5 h / 20 °C 4.1: potassium hydroxide / tert-butyl alcohol / 70 °C View Scheme

1.1: sec.-butyllithium / cyclohexane; tetrahydrofuran / 1.17 h / -78 °C 1.2: 0.58 h / -78 °C 2.1: triethylamine; copper(l) iodide / bis-triphenylphosphine-palladium(II) chloride / tetrahydrofuran / 5 h / 20 °C 3.1: potassium hydroxide / tert-butyl alcohol / 70 °C View Scheme

1: triethylamine; copper(l) iodide / bis-triphenylphosphine-palladium(II) chloride / tetrahydrofuran / 5 h / 20 °C 2: potassium hydroxide / tert-butyl alcohol / 70 °C View Scheme