Question

Explain any chemical/physical reactions occuring within the process of isolating Guaifenesin from two cough tablets. How does this isolation process work? The two tablets were crushed into powder and dissolved in 5mL ethyl acetate. The suspension was mechanically stirred for ten minutes, and then filtered through gravity filtration. 50mL hexanes were added to the filtrate, producing Guaifenesin. The solution is cooled in an ice bath for 45 minutes. Vacuum filtration collects the formed solid.

Answer 1

There is no chemical during the above process. It is a simple extraction of acive component i.e. Guaifenesin. When crushed tablet is dissolved in ethyl acetate and stirred for 10 minutes, the active organic compound Guaifenesin will dissolve in the ethylacetate and other inorganic excipients will remain insoluble. When it is filtered the dissolved Guaifenesin can be separated in filtrate from other insoluble materials. When it is kept in an ice bath after adding hexane to it, the Guaifenesin will form the crystal. Since it is a polar molecule containing two polar hydroxyl group, it will not be freely soluble in hexane. Pure Guaifenesin solid can be obtained after filteration.