To demonstrate the formation of 3-methoxyheptane through an SN2 mechanism, follow these steps:
1. Identify the nucleophile and electrophile: The nucleophile is the methoxide ion (CH3O-) and the electrophile is the alkyl halide, such as 1-chloroheptane (C7H15Cl).
2. Show the electron flow using curved arrows: Draw a curved arrow from the lone pair on the oxygen atom of the methoxide ion to the carbon atom bonded to the chlorine in 1-chloroheptane. This arrow represents the nucleophilic attack.
3. Show the leaving group departure: Draw another curved arrow from the carbon-chlorine bond in 1-chloroheptane to the chlorine atom. This arrow represents the departure of the chloride ion (Cl-) as the leaving group.
4. Draw the final product with the correct stereochemistry: As SN2 reactions lead to inversion of stereochemistry, if the starting 1-chloroheptane had an R configuration, the final product, 3-methoxyheptane, would have an S configuration (and vice versa). So, draw the final product with the methoxy group (OCH3) attached to the third carbon atom of the heptane chain, and the correct stereochemistry based on the starting material.
The resulting structure will be 3-methoxyheptane, with the appropriate stereochemistry.