Question

Homeworklib Question.docx

Answer 1

The Fischer esterification coverts the carboxylic acids and alcohols directly to esters by the acid catalyzed nucleophilic acyl substitution. The acid catalyst protonates the carbonyl oxygen and next the alcoholic group attacks the carbonyl carbon followed by the loss of proton gives the hydrate of an ester. Now, protonation of either of the hydroxy groups allows it to leave as water forming a resonance stabilized cation and finally by the loss of proton from the second hydroxy group gives the ester. Thus, the formation of intermediate and the product is shown in the following curved arrow mechanism. : O :OH OH H+ OH

: он : OH он CH3 tetrahedral intermediate Ht :OH O-CH3 OH2 :0 CH3 CH3