Synthesis of 3-bromo-4-methyl-styrene

Potassium hydrogen sulfate (0.55 g, 34 mmol), hydroquinone (0.142g, 1.3 mmol), and l-(3-bromo-4-methyl-phenyl)-ethanol (17.2 g, 80 mmol) were delivered into a 25-mL round bottomed flask, equipped with a distillation equipment. The mixture was kept stirring. 

The system was evacuated to 3 mm Hg. The dehydration and distillation processes 102 °C (3 mm Hg) proceeded at the same time. The isolated product was obtained in 13.6 g (86% yield). 

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