Nucleophilic Acyl Substitution: The Synthesis of Esters
Razon, Valjean Paulo Mella
Rico, Fatima Sarah Rogel
Institute of Chemistry, University of the Philippines, Diliman, Quezon City 1101 Philippines …show more content…
This objective was accomplished when the researchers synthesized esters of raspberry, banana and peach through reacting indicated alcohols and carboxylic acids in the presence of an acid catalyst in a round bottom flask and reflux condenser. This enabled the researchers to synthesize the following esters: pentan-2-yl acetate, benzyl acetate, butan-2-yl methanoate. The researchers, however, were unable to purify the said crude product due to the instructions given to them by their instructor. Therefore, the main objective of the experiment was observed, while the purification of the crude esters through simple distillation was not. The yield at the end of the experiment was not 100% percent due to certain factors in the natural process of synthesis and the technical failures within the experiment. Because of this, future researchers are advised to add smaller amounts of NaHCO3 to avoid clogging of the separatory funnel. Also the product must be fully stratified, with only the organic and aqueous layer visible, before separation of these. In addition, all of the procedures should be followed to facilitate a smooth flow of the experiment and the results and yields would be favorable. Also more time should be allotted for this experiment to have more favorable …show more content…
Ester. 2008. 19 February 2012 <http://science.jrank.org/pages/2572/Ester.html>.
Romero, Maria Dolores et al. "Study of the Influence of Alsohols in the Synthesis of Short Chain Esters." Chemical Engeneering Transactions 24 (2011): 37-42.
Silberberg. Principles of General Chemistry . Philippines: MC Graw Hill companies , 2010 .
Zimmerman, Isaak. Organic Chemistry. Benziger Bruce & Glencoe, Inc, 1997.
IUPAC. Compendium of Chemical Terminology, 2nd ed. (the "Gold Book"). Compiled by A. D. McNaught and A. Wilkinson. Blackwell Scientific Publications, Oxford (1997). XML on-line corrected version: http://goldbook.iupac.org (2006-) created by M. Nic, J. Jirat, B. Kosata; updates compiled by A. Jenkins. ISBN 0-9678550-9-8. doi:10.1351/goldbook.
Appendices :
Appendix A Answers to Questions 1. Le Chatelier’s Principle states that if a dynamic equilibrium is disturbed by changing the conditions, the position of the equilibrium moves to counteract the change. At equilibrium point, a substantial amount of ester, alcohol, water and carboxylic acid was present in the round bottom flask. So to ensure a reasonable yield of the ester, an excess of the alcohols (2-pentanol, 2-butanol and benzyl alcohol) was used to drive the reaction faster. Acetic acid was used as the limiting reagent. The alcohol was used in excess. The researchers suggest removal of water via azeotropic
Razon, Valjean Paulo Mella
Rico, Fatima Sarah Rogel
Institute of Chemistry, University of the Philippines, Diliman, Quezon City 1101 Philippines …show more content…
This objective was accomplished when the researchers synthesized esters of raspberry, banana and peach through reacting indicated alcohols and carboxylic acids in the presence of an acid catalyst in a round bottom flask and reflux condenser. This enabled the researchers to synthesize the following esters: pentan-2-yl acetate, benzyl acetate, butan-2-yl methanoate. The researchers, however, were unable to purify the said crude product due to the instructions given to them by their instructor. Therefore, the main objective of the experiment was observed, while the purification of the crude esters through simple distillation was not. The yield at the end of the experiment was not 100% percent due to certain factors in the natural process of synthesis and the technical failures within the experiment. Because of this, future researchers are advised to add smaller amounts of NaHCO3 to avoid clogging of the separatory funnel. Also the product must be fully stratified, with only the organic and aqueous layer visible, before separation of these. In addition, all of the procedures should be followed to facilitate a smooth flow of the experiment and the results and yields would be favorable. Also more time should be allotted for this experiment to have more favorable …show more content…
Ester. 2008. 19 February 2012 <http://science.jrank.org/pages/2572/Ester.html>.
Romero, Maria Dolores et al. "Study of the Influence of Alsohols in the Synthesis of Short Chain Esters." Chemical Engeneering Transactions 24 (2011): 37-42.
Silberberg. Principles of General Chemistry . Philippines: MC Graw Hill companies , 2010 .
Zimmerman, Isaak. Organic Chemistry. Benziger Bruce & Glencoe, Inc, 1997.
IUPAC. Compendium of Chemical Terminology, 2nd ed. (the "Gold Book"). Compiled by A. D. McNaught and A. Wilkinson. Blackwell Scientific Publications, Oxford (1997). XML on-line corrected version: http://goldbook.iupac.org (2006-) created by M. Nic, J. Jirat, B. Kosata; updates compiled by A. Jenkins. ISBN 0-9678550-9-8. doi:10.1351/goldbook.
Appendices :
Appendix A Answers to Questions 1. Le Chatelier’s Principle states that if a dynamic equilibrium is disturbed by changing the conditions, the position of the equilibrium moves to counteract the change. At equilibrium point, a substantial amount of ester, alcohol, water and carboxylic acid was present in the round bottom flask. So to ensure a reasonable yield of the ester, an excess of the alcohols (2-pentanol, 2-butanol and benzyl alcohol) was used to drive the reaction faster. Acetic acid was used as the limiting reagent. The alcohol was used in excess. The researchers suggest removal of water via azeotropic