Question

Ethers can often be prepared by SN2 reaction of alkoxide ions,${\mathbf{RO}}^{-}$ ,with alkyl halides. Suppose you wanted to prepare cyclohexyl methylether. Which of the two possible routes shown below would youchoose? Explain.

Short answer

In a Bimolecular Nucleophilic substitution chemical reaction,substituting an optically active compound with the nucleophile through a backside attack forms the product of inversion stereochemistry.

This reaction occurs in a polar aprotic solvent, e.g., acetone

Step-by-step solution

Bimolecular Nucleophilic substitution chemical reaction (SN2)

In a Bimolecular Nucleophilic substitution chemical reaction,substituting an optically active compound with the nucleophile through a backside attack forms the product of inversion stereochemistry.

This reaction occurs in a polar aprotic solvent, e.g., acetone

 Preparation of Cyclohexyl methyl ether

Cyclohexyl methyl ether is formed by two methods shown as follows:

• cyclohexanolate reacted with Iodomethane$\left({\text{S}}_{\text{N}}\text{2reaction}\right)$ forms the desired product methylcyclohexane, and this is an excellent method of preparing desired ether as Iodomethane is very much reactive in${\text{S}}_{\text{N}}2$ displacement reaction.

An excellent method for the formation of methoxyhexane

• Iodocyclohexane is a secondary haloalkane that reacts with base methoxide ion, forms the substituted product methoxyhexane, and the elimination product cyclohexene. This method forms other side products and the desired product; thus is a less satisfactory method for preparing ether

Less satisfactory method for the formation of methoxyhexane