Nucleophilic Substitution Reactions at the Saturated C Atom

摘要: Nucleophiles are usually anions or neutral species but not cations. This chapter focuses on the nucleophilic substitution reactions at saturated, that is, sp 3 -hybridized, C atom (abbreviated “S N reactions”). In these reactions, alkyl groups transferred to nucleophiles. Organic electrophiles of this type referred as alkylating agents. It is possible distinguish between good and poor nucleophiles when SN carried out competition experiments. There made available mixtures a standard agent. The nucleophile reacts form main product then “better” nucleophile. Within group attack electrophile with same atom, nucleophilicity decreases decreasing basicity Hammond postulate implies leaving stabilized species, high-energy species. Therefore weak, strong, bases. contrast S 2 mechanism, structure transition state rate-determining step in 1 mechanism cannot be depicted simple way. As an aid, one therefore uses model.