Ethylene Glycol → 6-Bromo-2-tetralone ethylene ketal

Participants

Reaction Steps

A mixture of 6-bromo-2-tetralone (8.80 g, 39 mmol), trimethyl orthoformate (17.2 ml, 157 mmol), ethylene glycol (16.2 ml, 290 mmol) and p-toluenesulfonic acid (0.07 g, 0.37 mmol) in dry dichloromethane (200 ml) was stirred at room temperature for 18 h, then partitioned between saturated aqueous NaHCO3 (100 ml) and dichloromethane (2×50 ml). The combined organic extracts were dried (Na2SO4) then evaporated in vacuo to give an oil. Column chromatography on silica with 0-10% diethyl ether-hexane gradient elution gave 6-bromo-2-tetralone ethylene ketal as a yellow oil (8.84 g, 84%).

Provenance & Evidence