SN1 and SN2 Reactions

Summary

The content provides an in-depth exploration of SN1 and SN2 reactions, detailing their mechanisms, kinetics, stereochemistry, and factors influencing their rates.

SN1 reactions are unimolecular nucleophilic substitutions characterized by a two-step mechanism where the rate-determining step is the loss of the leaving group, leading to a carbocation intermediate.
The stereochemistry of SN1 reactions often results in racemization, especially when starting with optically active compounds, due to the planar nature of the carbocation intermediate allowing nucleophilic attack from either side.
SN2 reactions are bimolecular nucleophilic substitutions with a single step mechanism where the nucleophile attacks the substrate simultaneously as the leaving group departs, generally leading to inversion of configuration.
Factors that favor SN1 reactions include highly substituted carbons, polar protic solvents, and weak bases as leaving groups, while SN2 reactions are favored by primary carbons, non-polar aprotic solvents, and small nucleophiles.
The choice between SN1 and SN2 mechanisms can be influenced by the substrate structure, the solvent, the leaving group, and the nucleophile.

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