Synthesis of Esters
SYNTHESIS OF ESTERS USING GREEN AND NON-GREEN CHEMISTRY
Abstract
Esters are a class of organic compounds with the general formula RCOOR’. Ester also contributes the flavor and aromas in fruits and flowers. The esterification reactions will use in the procedure, which are the interaction of a carboxylic acid with an alcohol, aided by an inorganic acid catalyst (H2SO4). Moreover, the green method will not use any catalyst but using heating source instead (microwave). Based on the comparison of two methods, green chemistry is the effective method because reduce the consumption energy and less time consuming than the non-green chemistry preparation.
Introduction
Esters are among the most widespread of all naturally occurring compounds. Many simple esters are pleasant-smelling liquids that are responsible for the fragrant odors of fruits and flowers. Examples are benzyl acetate, which is finding in orange oil, and isopentyl acetate, which is the part of banana oil. The ester linkage is also present in animal fats and in many biologically important molecules. Esters can be formed from both organic and inorganic acids and the process of producing an ester is called an Esterification. Esters of organic acids are usually colorless, neutral liquids, pleasant-smelling and generally insoluble in water but readily soluble in organic solvents. Esters are prepared synthetically in large quantities for commercial use as artificial fruit essences and other flavorings and as components of perfumes. Esterification is used to derivatize carboxylic acids and other acidic functional groups. In a typical reaction, Esterification involves the condensation of the carboxyl group of an acid and the hydroxyl group of an alcohol, with the elimination of water (Konwar, 2008). Many Esterification reactions are slow and elevated temperatures are frequently used. Since the Esterification reaction is an equilibrium reaction, it may be necessary to remove the water generated during
Abstract
Esters are a class of organic compounds with the general formula RCOOR’. Ester also contributes the flavor and aromas in fruits and flowers. The esterification reactions will use in the procedure, which are the interaction of a carboxylic acid with an alcohol, aided by an inorganic acid catalyst (H2SO4). Moreover, the green method will not use any catalyst but using heating source instead (microwave). Based on the comparison of two methods, green chemistry is the effective method because reduce the consumption energy and less time consuming than the non-green chemistry preparation.
Introduction
Esters are among the most widespread of all naturally occurring compounds. Many simple esters are pleasant-smelling liquids that are responsible for the fragrant odors of fruits and flowers. Examples are benzyl acetate, which is finding in orange oil, and isopentyl acetate, which is the part of banana oil. The ester linkage is also present in animal fats and in many biologically important molecules. Esters can be formed from both organic and inorganic acids and the process of producing an ester is called an Esterification. Esters of organic acids are usually colorless, neutral liquids, pleasant-smelling and generally insoluble in water but readily soluble in organic solvents. Esters are prepared synthetically in large quantities for commercial use as artificial fruit essences and other flavorings and as components of perfumes. Esterification is used to derivatize carboxylic acids and other acidic functional groups. In a typical reaction, Esterification involves the condensation of the carboxyl group of an acid and the hydroxyl group of an alcohol, with the elimination of water (Konwar, 2008). Many Esterification reactions are slow and elevated temperatures are frequently used. Since the Esterification reaction is an equilibrium reaction, it may be necessary to remove the water generated during
References: Konwar, Dilip. Esterification of Carboxylic Acids by Acid Activated Kaolinite Clay. Indian Journal of Chemical Technology: Vol.15, January 2008: pp. 75-78. Retrieved June 9, 2010. <http://nopr.niscair.res.in/bitstream/123456789/872/1/IJCT%2015%281%29%20%282008%29%2075-78.pdf> Preparation of 3-Methylbytylacetate (Banana Oil) in the Microwave Oven. Uoregon. Retrieved April 10, 2010 <http://greenchem.uoregon.edu/ACSGoingGreenSite/PDFs/20050315TuesPM/1339BrownLab.pdf >. Sanghi, Rashmi, and M M Srivastava. Green Chemistry: Environment Friendly Alternatives. United Kingdom: Alpha Science International Ltd, 2003. Synthesis of banana oil. Umsl. Retrieved April 10, 2010 < http://www.umsl.edu/ ~orglab/experments/Bananaoil.html >. Wilkes, Charles E., James W. Summers, and Charles A. Daniels. PVC Handbook. Canada: Hanser Gardner Publications, 2005.