1: N-iodo-succinimide; [bis(acetoxy)iodo]benzene; palladium diacetate / 1,2-dichloro-ethane / 1.5 h / 65 °C / Inert atmosphere 2: silver fluoride / tetrahydrofuran; water / 20 °C / Inert atmosphere; Darkness View Scheme

Multi-step reaction with 2 steps 1.1: n-butyllithium / hexanes; diethyl ether / 0.67 h / -78 °C / Inert atmosphere1.2: -78 - 20 °C / Inert atmosphere2.1: n-butyllithium / tetrahydrofuran; hexanes / -78 °C / Inert atmosphere2.2: -78 - 30 °C / Inert atmosphere