Fischer esterification or Fischer–Speier esterification is a special type of esterification by reducing (eliminating a water molecule, dehydration) a carboxylic acid and an alcohol in the presence of an acid catalyst. The reaction was first described by Emil Fischer and Arthur Speier in 1895. Most carboxylic acids are suitable for the reaction, but the alcohol should generally be a primary or secondary alkyl. Tertiary alcohols are prone to elimination.
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