Glyoxylic Acid → 4-tert-Butyl-2,6-dimethylmandelic acid acetate

Beteiligte Stoffe

Reaktionsbedingungen

Reaktionsschritte

A mixture of 89 g of 50% aqueous glyoxylic acid solution [0.6 mol], 400 ml of glacial acetic acid and 81.1 g [0.5 mol] of 1-tert-butyl-3,5-dimethylbenzene is initially charged. Starting at room temperature, 85.8 g of 96% strength sulfuric acid [0.84 mol] are added dropwise over a period of 15 minutes, during which time the temperature of the reaction mixture increases to about 35° C. The mixture is heated to 60° C. and stirred at this temperature for 9 hours. The cooled reaction mixture is then stirred into 750 ml of ice-water. The mixture is extracted three times with in each case 150 ml of methylene chloride, the combined organic phases are washed with 100 ml of saturated aqueous NaCl solution, dried over sodium sulfate and concentrated under reduced pressure. This gives 136.7 g of a yellowish thick oil, which, according to GC/MS(sil.), has the following composition:

Herkunft & Nachweise