Final answer:
The saponification of methyl m-nitrobenzoate with NaOH breaks the ester bond to form m-nitrobenzoic acid and methanol.
Step-by-step explanation:
The mechanism for the saponification of methyl m-nitrobenzoate involves its reaction with a strong base, such as sodium hydroxide (NaOH), resulting in the formation of m-nitrobenzoic acid and methanol.
Saponification is the alkaline hydrolysis of esters, and in this case, methyl m-nitrobenzoate is hydrolyzed. The ester bond is cleaved by the hydroxide ions from NaOH, which attacks the carbonyl carbon, forming a tetrahedral intermediate.
This intermediate then collapses, leading to the departure of methanol as a leaving group and the formation of m-nitrobenzoate anion, which upon protonation gives m-nitrobenzoic acid.