Q.16 - Organic Chemistry

Question

Draw both the ${\mathbf{\text{S}}}_{\mathbf{\text{N}}}\mathbf{\text{1}}$ and E1 products of each reaction.

a.

b.

Step-by-Step Solution

Answer

The ${\text{S}}_{\text{N}}\text{1}$ and E1 products from each reaction are given below:-

Definition of S N 1 reaction

The two-steps process reaction formed by the formation of the carbocation, followed by the attack of a nucleophile to replace the leaving group, is known as ${\mathbf{\text{S}}}_{\mathbf{\text{N}}}\mathbf{\text{1}}$ reaction.

In this reaction, a nucleophile takes the place of a leaving group. Since the rate of a reaction depends only on the concentration of the substrate, hence a unimolecular substitution reaction.

Definition of E1 reaction

An E1 reaction is a two-step process reaction formed by the formation of the carbocation and the loss of a proton from $\mathbf{\text{β}}$ carbon and a leaving group takes place to form an alkene.

The rate of a reaction depends only on the concentration of the substrate hence a unimolecular elimination reaction.

Types of base/nucleophile use

Weak bases and weak nucleophiles promote a mixture of both ${\text{S}}_{\text{N}}\text{1}$ and E1 reactions. Both water and ethanol are a weak base and a weak nucleophile. Hence the products formed are both ${\text{S}}_{\text{N}}\text{1}$ and E1 products.

 

Hence, considering all the explanations, the ${\text{S}}_{\text{N}}\text{1}$ and E1 products from each reaction are given below:-

Products of reaction a

A substitution and an elimination product are formed from the above reaction scheme.

Products of reaction b

The above reaction scheme yields a substitution and an elimination product.