Guaifenesin
Synthesis and Isolation of Expectorant Guaifenesin
By: Ben DuBose
Dr. Cossey
3361L
Abstract The purpose of this experiment was to isolate and synthesize Guaifenesin. Isolation was performed with the use of two Guai-Aid Tablets, each of which contained 400mg of pure Guaifenesin. Reflux, a technique used to heat a mixture without evaporating the solution, was used to synthesize Guaifenesin through a Williamson Ether Synthesis reaction with an SN2 mechanism.
Introduction
In this two-week experiment, guaifenesin, an expectorant found in over-the-counter cough syrups and tablets, was prepared through the Williamson Ether Synthesis model. The model involved an SN2 mechanism between the sodium phenoxide salt derived from guaiacol (2-methoxyphenol) and 3-chloro-1,2-propanediol (Wildman, 2003). With the Williamson Ether Synthesis specializing in producing ethers, it was ideal for this lab because of the alcohol and the alkyl halide used. After the synthesis and isolation of Gauifenesin was completed, the melting point ranges were observed and percentage yields were calculated to compare with the values of authentic guaifenesin and guaiacol. Reflux was used to synthesize Guaifenesin. Guaifenesin is an expectorant, meaning it helps loosen congestion in one’s chest and throat, making it easier to cough. Guaifenesin is used to reduce chest congestion caused by the common cold, infections, or allergies. It allowed ciliary movement to carry the loosened secretions, which prevent build up in the respiratory tract (London, 2014). Throat aid is not the only use, however Guaifenesin has also been promoted to facilitate conception right before ovulation by thinning and increasing the cervical mucus (Early-Pregnancy-Tests.com).
Procedure 550 ul guaiacol was dissolved in 3 mL of 95% ethanol and then 1 mL of 6.25 M aqueous NaOH was added to the solution and refluxed. 500 ul 3-chloro-1,2-propanediol was dissolved into 0.5 mL
By: Ben DuBose
Dr. Cossey
3361L
Abstract The purpose of this experiment was to isolate and synthesize Guaifenesin. Isolation was performed with the use of two Guai-Aid Tablets, each of which contained 400mg of pure Guaifenesin. Reflux, a technique used to heat a mixture without evaporating the solution, was used to synthesize Guaifenesin through a Williamson Ether Synthesis reaction with an SN2 mechanism.
Introduction
In this two-week experiment, guaifenesin, an expectorant found in over-the-counter cough syrups and tablets, was prepared through the Williamson Ether Synthesis model. The model involved an SN2 mechanism between the sodium phenoxide salt derived from guaiacol (2-methoxyphenol) and 3-chloro-1,2-propanediol (Wildman, 2003). With the Williamson Ether Synthesis specializing in producing ethers, it was ideal for this lab because of the alcohol and the alkyl halide used. After the synthesis and isolation of Gauifenesin was completed, the melting point ranges were observed and percentage yields were calculated to compare with the values of authentic guaifenesin and guaiacol. Reflux was used to synthesize Guaifenesin. Guaifenesin is an expectorant, meaning it helps loosen congestion in one’s chest and throat, making it easier to cough. Guaifenesin is used to reduce chest congestion caused by the common cold, infections, or allergies. It allowed ciliary movement to carry the loosened secretions, which prevent build up in the respiratory tract (London, 2014). Throat aid is not the only use, however Guaifenesin has also been promoted to facilitate conception right before ovulation by thinning and increasing the cervical mucus (Early-Pregnancy-Tests.com).
Procedure 550 ul guaiacol was dissolved in 3 mL of 95% ethanol and then 1 mL of 6.25 M aqueous NaOH was added to the solution and refluxed. 500 ul 3-chloro-1,2-propanediol was dissolved into 0.5 mL
References: 1.) Wildman, R., & Coleman, W. (2003, March 1). Featured Molecules: Enantiomers of Guaifenesin. Retrieved November 13, 2014, from http://pubs.acs.org/doi/abs/10.1021/ed080p315 2.) London, M. (2014, June 16). The Truths and Myths of the use of Guaifenesin for Fibromyalgia. Retrieved November 13, 2014, from http://web.mit.edu/london/www/guai.html 3.) Guaifenesin, FertileCM, and Cervical Mucus. (n.d.). Retrieved November 22, 2014, from http://www.early-pregnancy-tests.com/guaifenesin.html 4.) Iverson. (n.d.). SN2 Reaction. Retrieved November 22, 2014, from http://iverson.cm.utexas.edu/courses/310N/ReactMoviesFl05 /SN2text.html 5.) James. (2014, January 1). The Williamson Ether Synthesis. Retrieved November 22, 2014, from http://www.masterorganicchemistry.com/2014/10/24/the- williamson-ether-synthesis/ 6.) McConathy, J., & Owens, M. (2003, April 25). Stereochemistry in Drug Action. Retrieved November 22, 2014, from http://www.ncbi.nlm.nih.gov/pmc/articles/PMC353039/