Name: Tests for Alcohols
Uploaded: 2019-07-19
Duration: 8 min 25 s
Description: Do you know there are certain sets of chemical reactions that determine the chemical characteristics of alcohols? Such reactions can be used to identify give...

Question

Choose the reaction in each of the following pairs that proceeds at the faster rate. Explain your reasoning:

Base-promoted hydrolysis of $m$ -nitrophenyl acetate or $p$ -nitrophenyl acetate.

Accepted Answer

Hydrolysis of an ester is the addition-elimination reaction of esters, and the product are carboxylic acid, phenol and its derivative.

Since the medium is basic hence, it will convert into the salt of acid.

During the reaction, nucleophile (base) will attack at the electrophilic carbon of the ester.

Hydrolysis of $p ‐$ nitro phenyl acetate:

Hydrolysis of $m ‐$ nitro phenyl acetate:

The rate of reaction depends on the leaving ability of the leaving group. More the stabliity of the leaving group, more will be the rate of reaction.

The leaving group is a negatively charged ion so, it is stabilised by the electron withdrawing group present in the compound.

$m$ -nitro phenyl acetate contains the nitro group which shows a negative inductive effect. Hence, it is more stable than the phenyl acetate.

When the nitro group is present at the para position, phenoxide ion is stabilised by $- M$ effect of the nitro group hence, it is more stable than -meta nitrophenol.

It is explained by the following resonating structure.

So, the rate of hydrolysis is more in the para nitro phenol.

Choose the reaction in each of the following pairs that proceeds at the faster rate. Explain your reasoning:

Base-promoted hydrolysis of $m$ -nitrophenyl acetate or $p$ -nitrophenyl acetate.

Important Questions on Alcohols, Phenols and Ethers

Learn and Prepare for any exam you want !

Choose the reaction in each of the following pairs that proceeds at the faster rate. Explain your reasoning: Base-promoted hydrolysis of m-nitrophenyl acetate or p-nitrophenyl acetate.

Important Questions on Alcohols, Phenols and Ethers

Learn and Prepare for any exam you want !

Choose the reaction in each of the following pairs that proceeds at the faster rate. Explain your reasoning:

Base-promoted hydrolysis of $m$ -nitrophenyl acetate or $p$ -nitrophenyl acetate.