what are the reactions present in reacting benzocaine with 2-diethylaminoethanol using na+oet- to produce procaine?
To determine the reactions involved in the conversion of benzocaine to procaine using 2-diethylaminoethanol and NaOEt, we need to consider the functional groups present in each compound and their reactivity.
Benzocaine (ethyl 4-aminobenzoate) contains an ester group (COO) and an amine group (NH2). On the other hand, procaine (2-diethylaminoethyl 4-aminobenzoate) contains an ester group, an amine group, and an additional amine-containing side chain.
Here's a step-by-step explanation of the reactions involved:
1. Deprotonation and formation of the sodium alkoxide:
Sodium ethoxide (NaOEt) dissociates in polar solvents like ethanol to give sodium ions (Na+) and ethoxide ions (OEt-). In this case, NaOEt reacts with ethanol to form the sodium alkoxide (NaOEt) in situ. The alkoxide acts as a strong base and nucleophile in subsequent steps.
2. Ester cleavage:
Sodium alkoxide (NaOEt) reacts with the ester group of benzocaine, resulting in the cleavage of the ester bond. The alkoxide acts as a nucleophile attacking the carbonyl carbon of the ester group, leading to the formation of ethyl 4-aminobenzoate (benzocaine) and the corresponding alcohol (2-diethylaminoethanol).
3. N-Alkylation:
The nucleophilic amine group of 2-diethylaminoethanol attacks the electronegative quaternary carbon atom (carbon bearing the positive charge) in benzocaine. This reaction is known as N-alkylation and results in the substitution of the ethyl group with the 2-diethylaminoethyl group, forming procaine.
Overall, the reactions can be summarized as follows:
Benzocaine + NaOEt + 2-diethylaminoethanol ⟶ Procaine + Ethanol + NaOH
It's important to note that the reaction conditions such as temperature, solvent, and stoichiometry can influence the outcome of the reaction, and additional purification steps might be required to obtain pure procaine.