nucleophilic substitution

why does nucleophilic substitution occur?

• in a haloalkane, the C-halogen bond is polar

• this means the δ⁺ C is attacked by nucleophiles which replace the halogen

what is a nucleophile?

a species attracted to areas w/ low e- levels, meaning they are lone pair donors

give 3 examples of nucleophiles:

• OH^- (reagent = NaOH/KOH)

• CN^- (reagent = KCN)

• NH₃

draw the mechanism for nuc sub w/ chloroethane and NaOH/KOH:

draw the mechanism for nuc sub w/ bromoethane and ethanolic KCN:

what can nuc sub form and how?

• alcohols by reacting w/ NaOH/KOH - OH^-

• nitriles by reacting w/ ethanolic KCN - CN^-

• amines by reacting w/ ethanolic NH₃ - NH₃

draw the mechanism for nuc sub of 1-chloropropane and XS ethanolic NH₃:

which solvent is the reagent dissolved in nuc sub?

aqueous

what temperature is a nuc sub reaction carried out at?

cold

which type of haloalkane is most likely to carry out nuc sub?

primary

what is a primary haloalkane?

a haloalkane w/ 1 C atom bonded directly to the C atom which is bonded to the halogen