1: potassium hydroxide / dimethyl sulfoxide / 5 h / 20 °C 2: pyridinium chlorochromate / dichloromethane / 3 h / 20 °C 3: dichloromethane / 3 h / -10 - 25 °C / Inert atmosphere View Scheme

1: pyridinium chlorochromate / dichloromethane / 3 h / 20 °C 2: dichloromethane / 3 h / -10 - 25 °C / Inert atmosphere View Scheme

in dichloromethane T=-10 - 25°C; Wittig reaction; 3 h; Inert atmosphere;