1.1: tert-butyl alcohol / 30 - 40 °C / Inert atmosphere 2.1: n-butyllithium / tetrahydrofuran; hexane / 0.5 h / -78 °C / Inert atmosphere 2.2: -78 - -20 °C / Inert atmosphere 2.3: -78 - 20 °C / Inert atmosphere 3.1: trifluoroacetic acid / dichloromethane / 20 °C / Inert atmosphere 4.1: N-chloro-succinimide / acetonitrile / 2 h / Reflux; Inert atmosphere View Scheme

1.1: n-butyllithium / tetrahydrofuran; hexane / 0.5 h / -78 °C / Inert atmosphere 1.2: -78 - -20 °C / Inert atmosphere 1.3: -78 - 20 °C / Inert atmosphere 2.1: trifluoroacetic acid / dichloromethane / 20 °C / Inert atmosphere 3.1: N-chloro-succinimide / acetonitrile / 2 h / Reflux; Inert atmosphere View Scheme

1: trifluoroacetic acid / dichloromethane / 20 °C / Inert atmosphere 2: N-chloro-succinimide / acetonitrile / 2 h / Reflux; Inert atmosphere View Scheme