Synthesis of Aspirin and Oil of Wintergreen - …
Preparation of oil of wintergreen. - YouTube
2 reactions carried out:
H2SO4 – catalyzed
H3PO4 – catalyzed (less strong, less potentially harmful)
Micro-scale reaction – less waste
Extraction with diethyl ether (instead of methylene chloride) – less toxic Reflux-condensation setup: synthesis of wintergreen oil Salicylic acid, methanol, sulfuric/phosphoric acid
Stirred in hot water bath, while cooling steam with water current, for 60 minutes
Removed from heat, cooled to ambient temperature Liquid-Liquid extraction: Diethyl ether and DI water added to reaction mixture, organic layer (bottom) extracted
Organic layer washed 3x with sodium bicarbonate (vented to release CO2 gas), extracted after last wash, and solvent (ether) boiled off
NMR spectra analyses performed on remaining product (1) (2) Hartel, A.M.; Hanna, J.M.
Preparation of Oil of Wintergreen from Commercial …
Oil of Wintergreen (methyl salicylate)– aromatic ester, synthesized by Fischer Esterification.
Common learning lab, used to associate product with scent, gives experiment “immediate relevance” (Hartel & Hanna).
Most widely used technique for creating esters (Hartel & Hanna).
General reaction: Green Techniques...