1.1: tetraethylammonium p-toluenesulfonate; triethylamine / acetonitrile / 0.08 h / 20 °C / Electrochemical reaction 1.2: 0.25 h / 0 °C 2.1: triethylsilane; boron trifluoride diethyl etherate / dichloromethane / 1.5 h / 0 °C 3.1: potassium hydrogensulfate / anhydrous xylene / 6 h / Reflux View Scheme

1.1: N,N-dimethyl-formamide / 50 °C 2.1: tetraethylammonium p-toluenesulfonate; triethylamine / acetonitrile / 0.08 h / 20 °C / Electrochemical reaction 2.2: 0.25 h / 0 °C 3.1: triethylsilane; boron trifluoride diethyl etherate / dichloromethane / 1.5 h / 0 °C 4.1: potassium hydrogensulfate / anhydrous xylene / 6 h / Reflux View Scheme

1: methanol / 1 h / UV-irradiation; Inert atmosphere 2: toluene-4-sulfonic acid / acetonitrile / 24 h / 20 °C View Scheme

in methanol 1 h; UV-irradiationInert atmosphere;