2,6-dimethylpyridine; oxoammonium salt in dichloromethane T=20°C; Sealed tube;

1: 4-ethynyl-1-methoxy-benzene With n-butyllithium in tetrahydrofuran; hexane T=-78°C; 0.5 h; 2: ethyl-α,α,α-trifluoroacetate With boron trifluoride diethyl etherate in tetrahydrofuran; hexane T=-78°C; 1.5 h;

1.1: bis-triphenylphosphine-palladium(II) chloride; copper(l) iodide; triethylamine / 18 h / 20 °C / |Inert atmosphere 2.1: silica gel / dichloromethane / 24 h / 20 °C 3.1: tetrahydrofuran / 0.17 h / 0 °C / |Inert atmosphere; |Sealed tube 3.2: 0 - 20 °C / |Inert atmosphere; |Sealed tube 3.3: 0 - 20 °C / |Inert atmosphere; |Sealed tube 4.1: oxoammonium salt; 2,6-dimethylpyridine / dichloromethane / 20 °C / |Sealed tube View Scheme

1.1: silica gel / dichloromethane / 24 h / 20 °C 2.1: tetrahydrofuran / 0.17 h / 0 °C / |Inert atmosphere; |Sealed tube 2.2: 0 - 20 °C / |Inert atmosphere; |Sealed tube 2.3: 0 - 20 °C / |Inert atmosphere; |Sealed tube 3.1: oxoammonium salt; 2,6-dimethylpyridine / dichloromethane / 20 °C / |Sealed tube View Scheme

1.1: tetrahydrofuran / 0.17 h / 0 °C / |Inert atmosphere; |Sealed tube 1.2: 0 - 20 °C / |Inert atmosphere; |Sealed tube 1.3: 0 - 20 °C / |Inert atmosphere; |Sealed tube 2.1: oxoammonium salt; 2,6-dimethylpyridine / dichloromethane / 20 °C / |Sealed tube View Scheme