Final answer:
E2 eliminations typically compete with SN2 reactions, with the outcome depending on the substrate structure, sterics, and base strength.
Step-by-step explanation:
E2 eliminations typically compete with SN2 reactions.
In E2 reactions, elimination of a leaving group and a proton occurs simultaneously. This bimolecular reaction mechanism involves the base acting as both a nucleophile and a proton acceptor. On the other hand, in SN2 reactions, the nucleophile directly replaces the leaving group in a single step.
The competition between E2 and SN2 reactions depends on factors such as the structure of the substrate, steric hindrance, and the strength of the base. Secondary substrates can undergo both E2 and SN2 reactions, whereas primary and methyl substrates predominantly undergo SN2 reactions.