Acetaldehyde → 1,3-Dioxolane, 2-methyl-4-phenyl-

Beteiligte Stoffe

Reaktionsbedingungen

Reaktionsschritte

A 1 l stirrer fitted with reflux condenser, thermometer and dropping funnel was charged with 223 g (1.47 mol) of (±)-1-phenyl-1,2-ethanediol (3) (91% pure according to GC) from Example 1, 100 ml of diethyl ether and 2 g of para-toluenesulfonic acid and cooled to 5–10° C., and, at this temperature, 80.8 g (1.83 mol) of acetaldehyde were added over the course of 30 min. When the dropwise addition was complete, the mixture was then stirred firstly for 4 h at 5–10° C. and for a further 2 h at a maximum of 20° C. After this time, water was added, the organic phase was separated off, the aqueous phase was extracted with 1×100 ml of ether, and the combined organic phases were washed until neutral with sodium carbonate solution and water. Drying over Na2SO4 was then carried out, and the solvent was distilled off under reduced pressure.

Herkunft & Nachweise