How to Leverage Nucleophilic Addition Reactions – Part 3

A nucleophilic addition (AN) reaction is an addition reaction where an organic compound with an electrophilic double/triple bond reacts with a nucleophile s.t. the double/triple bond undergoes a cleavage.


It’s often followed by an elimination of a (good) leaving group.

Let’s remember that nucleophilicity and basicity are not the same thing!

Fischer esterification or Fischer–Speier esterification is an esterification reaction by refluxing a carboxylic acid and an alcohol in the presence of an acid catalyst.

Fischer esterification is typically an acid-catalyzed nucleophilic acyl substitution and stereoretentive.

Most carboxylic acids are suitable for the reaction, but the alcohol should generally be primary/secondary as tertiary alcohols are prone to elimination. Due to steric and/or electronic effects in carboxylic acids, the reaction rate may differ significantly.

Question:

Predict which of the following will be easily esterified and why. If the introduction of the ester group is slow, what would be your workaround to make it faster?



Click/tap to enlarge the image

Solution infographic:



Click/tap to enlarge the image

SN2 = Substitution nucleophilic bimolecular

Hindrance handled well❓ Let Chemaficionado know in the comments below or at mychemistryhomework@gmail.com❗

References:

(1)    Nucleophilic addition. Wikipedia. https://en.wikipedia.org/wiki/Nucleophilic_addition.

Wikipedia Contributors. Fischer–Speier esterification. Wikipedia.

(2)    Wikipedia Contributors. Fischer–Speier esterification. Wikipedia. https://en.wikipedia.org/wiki/Fischer%E2%80%93Speier_esterification.

‌(3)    Brown, C.; Ford, M. Higher Level Chemistry, 2nd ed.; Pearson Education: Harlow, Essex, 2014.

(4)    Ncert. Chemistry : Textbook for Class XII - Part.II; National Council Of Educational Research And Training: New Delhi.

(5)    Graham, T. W.; Fryhle, C. B.; Snyder, S. A. Organic Chemistry.; Hoboken, Nj John Wiley Et Sons, Inc, 2016.

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