Esterification (URGENT)(20pts)

esterfication is a condensation reaction,so it is exothermic=]
EsterificationFrom Wikipedia, the free encyclopedia
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Please help improve this article by adding citations to reliable sources. Unsourced material may bechallenged and removed. (December 2009)Esterification is the general name for a chemical reaction in which two reactants (typically an alcohol and an acid) form an ester as the reaction product. Esters are common in organic chemistry and biological materials, and often have a characteristic pleasant, fruity odor. This leads to their extensive use in the fragrance and flavor industry. Ester bonds are also found in many polymers.Esterification is a reversible reaction. Hydrolysis—literally "water splitting"—involves adding water and a catalyst (commonly NaOH) to an ester to get the sodium salt of the carboxylic acid and alcohol. As a result of this reversibility, many esterification reactions are equilibrium reactionsand therefore need to be driven to completion according to Le Chatelier's principle. Esterifications are among the simplest and most often performed organic transformations.The most common esterification processes involve nucleophilic acyl substitution where the carbonyl compound is used as an electrophile and is attacked by a nucleophilic alcohol. However, other processes are possible; esterification by alkylation reverses the roles of "classic" carbonyl chemistry: a carboxylate anion is used as a nucleophile that displaces a halide ion in an SN2 reaction.Contents [hide]1 Fischer esterification2 Reaction with acyl halides3 Reaction with acid anhydrides4 Alkylation of carboxylate salts5 Other methods6 See also[edit]Fischer esterification

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