Multi-step reaction with 4 steps 1.1: potassium hydroxide / ethanol / Inert atmosphere2.1: acetic acid / tetrachloromethane / Inert atmosphere2.2: Inert atmosphere3.1: piperidine; copper(l) iodide; bis-triphenylphosphine-palladium(II) chloride; triphenylphosphine / Inert atmosphere3.2: Inert atmosphere4.1: sodium hydroxide / tetrahydrofuran; methanol / Inert atmosphere