7. Substitution Reactions

Predict the product of the reaction

Predict the product of the reaction

For each reaction, give the expected substitution product, and predict whether the ­mechanism will be predominantly first order (SN1) or second order (SN2). Hint: The strength of the nucleophile (or base) usually determines the order of the reaction. Strong nucleophiles encourage bimolecular, second-order reactions, and weak nucleophiles more commonly react by unimolecular, first-order mechanisms. Also, SN2 is unlikely with 3° halides, and SN1 is unlikely with 1° halides unless they are resonance-stabilized. d. cyclohexylbromide + methanol e. Cyclohexylbromide + sodium ethoxide

Explain why the following alkyl halide does not undergo a substitution reaction, regardless of the base that is used.

Draw the substitution products for each of the following reactions; if the products can exist as stereoisomers, show what stereoisomers are obtained: c. benzyl chloride+CH3CH2OH d. allyl chloride+CH3OH

Draw the substitution products for each of the following reactions; if the products can exist as stereoisomers, show what stereoisomers are obtained: a. (R)-2-bromopentane+CH3O− b. (R)-3-bromo-3-methylheptane+CH3OH