SN2reaktioon

SN2 reaction is a fundamental organic chemistry concept. It stands for Substitution Nucleophilic Bimolecular, indicating a two-step reaction mechanism where the rate-determining step involves both the nucleophile and the substrate. In an SN2 reaction, a nucleophile, which is an electron-rich species, attacks an electrophilic carbon atom, displacing a leaving group. The "bimolecular" aspect means that the concentration of both the nucleophile and the substrate affects the reaction rate. The reaction proceeds with inversion of configuration at the carbon center, meaning the stereochemistry is flipped. This backside attack by the nucleophile is characteristic of the SN2 mechanism. Common substrates for SN2 reactions are primary and secondary alkyl halides, as well as alkyl sulfonates, where steric hindrance around the electrophilic carbon is minimized. Strong nucleophiles and polar aprotic solvents generally favor SN2 reactions. Primary alkyl halides are the most reactive towards SN2, followed by secondary. Tertiary alkyl halides are generally unreactive in SN2 reactions due to significant steric hindrance. Understanding SN2 reactions is crucial for predicting reaction outcomes and designing synthetic pathways in organic chemistry.