CH 6-5 SN1 Reaction – Part II Alkyl Halide Structure in SN1 Reactions

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Substitution and Elimination Reactions of Alkyl Halides.

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CH 6-5 SN1 Reaction – Part II Alkyl Halide Structure in SN1 Reactions Rank the following substrates in order of SN1 reactivity: (NR) Methyl, 1o <<<<< 2o << 3o Trend is consistent with carbonium ion stability.

Stereochemistry in The SN1 Reaction A Non-Stereospecific Reaction Racemic “Racemization”………………….WHY?

The Leaving Group in SN1 Reactions Since ionization of the substrate (i.e., the leaving group “leaves” on its own), the Leaving Group is very important in SN1 reactions, and MUST form a weak base: <<<< < < F- Cl- Br- I-

The Nucleophile in SN1 Reactions What are the most reactive nucleophiles in SN1 reactions? Rate = k [substrate] Neither the strength or concentration of the nucleophile have any effect on the rate of SN1 reactions! SN1 reactions typically use weak nucleophiles, and the solvent is often the source of the nucleophile – “solvolysis” reactions are SN1 reactions.