Question

In: Chemistry

The rate of the reaction of NH2OH with aldehydes and ketones is very sensitive to pH.

The rate of the reaction of NH2OH with aldehydes and ketones is very sensitive to pH. It is very low in solutions more acidic than pH 2 or more basic than pH 7. It is highest in moderately acidic solution (pH ∼ 4). Suggest explanations for these observations.

 

 

Solutions

Expert Solution

At pH around 4.0 is optimal pH for imine formation. At higher pH=>7, there is insufficient acid present and at lower pH =<2, the amine will be protonated rendering it unable to do a nucleophilic attack at the carbonyl carbon.

 

Hence, at moderately acidic condition (pH=4.0), speed is maximum for imine formation.

Hence, at moderately acidic condition (pH=4.0), speed is maximum for imine formation.

Junaid answered 2 years ago
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