Substitution & Elimination

common nucleophiles

polar APROTIC solvent trend

CARBON!

polar PROTIC solvent trend

IODINE!

SN2

• pentavalent 

• inversion

• rate: k{nucleophile} {electrophile} 

STRONG NUCLEOPHILE 

SN1

• secondary or tertiary 

• rate limiting step, carbocation rearrangement 

• racemic mixture 

• rate: k{electrophile}

WEAK NUCLEOPHILE 

E2

• leaving group and beta proton anti periplanar 

• steroselective

• rate: k{base}{electrophile}  

• STRONG base 

hindered base: HOFMANN

unhindered base: ZAITSEV 

E1 

• carbocation rearrangement 

• WEAK base, alcohols, water, heat 

• Zaitsev product, more substituted is favored 

strong nucleophile strong base

HO-, R-O-, deprotonated alcohol, R2N-, deprotonated amines

weak nucleophile strong base

KO-t-Bu, LDA

strong nucleophile weak base

R-NH2, R-S-, CN-, N3-, I-, RCOO-, H2S, R-SH

weak nucleophile weak base

H2O, R-OH, carboxylic acids

HEAT will undergo

E1

table