In an example of the SN2 reaction , the attack of Br − ( the nucleophile ) on an ethyl chloride ( the electrophile ) results in ethyl bromide , with chloride ejected as the leaving group . : SN2 attack occurs if the backside route of attack is not sterically hindered by substituents on the substrate .
In an example of the SN2 reaction , the attack of OH − ( the nucleophile ) on a bromoethane ( the electrophile ) results in ethanol , with bromide ejected as the leaving group : A SN2 reaction occurs if the backside route of attack is not blocked by other atoms in the molecule ( sterically hindered by substituents on the substrate ) .