1-Butanol → L-Tyrosine, butanoate (ester)

Participants

Reaction Steps

18.19 g of tyrosine was suspended in a solution of 9.8 g of concentrated sulfuric acid, 40 mL water, 40 mL of butanol, and 200 mL of toluene in a 500 mL round bottom flask equipped with a condenser and a Dean-Stark apparatus. The resulting solution was heated at reflux temperature until no more water could be distilled. The resulting solution was cooled in an ice bath, which caused the solution to separate into two phases. The upper phase was discarded and the lower phase, an oily syrup, was retained. The syrup was mixed with sufficient 5% aqueous sodium bicarbonate solution to neutralize acidic impurities to provide a solid that was collected by filtration and washed with cold water. The resulting solid was re-crystallized in ethyl acetate.

Provenance & Evidence