Benzyl Chloride → Dibenzyl ether

Participants

Reaction Steps

A mechanically stirred mixture of 104 g (0.78 mole) of (R,S)-2,2-dimethyl-4-hydroxymethyl-1,3-dioxolane, 500 ml of benzene, 86 g (1.53 mole) of powdered potassium hydroxide and 175 ml (1.52 mole) of benzyl chloride was refluxed for 17 hours while separating the condensed waterlayer (14 ml of water separated). After cooling the mixture was washed with water, 1M sodium hydrogen carbonate and brine respectively, dried with magnesium sulphate, filtered and evaporated to give 287 g of crude benzyl ether. This was stirred with a mixture of 300 ml of methanol, 100 ml of water and 20 ml of 36% hydrochloric acid for 1,5 hours. Next the mixture was neutralized with about 10 g of sodium hydroxide in water and concentrated in vacuum. The residue was extracted with diethyl ether and the extract was dried with magnesium sulphate, filtered and evaporated to give 163 g of residue. This was purified over silica to give 118 g of (R,S)-3 -benzyloxy-propane-1,2-diol.

Provenance & Evidence