Bases and Nucleophiles

Strong Nucleophiles/Bases

usually anions with a full negative charge (easily recognizable by the presence of sodium, lithium, or potassium counterions)

Strong Nucleophiles

participate in Sn2 substitutions

Strong Bases

participate in E2 type eliminations

Weak Nucleophiles

-typically neutral molecules

-participlate in Sn1 substitutions

Weak Bases

-typically neutral molecules

-participate in E1 eliminations

-can occur concurrently with Sn1

Strong, Non-Nucleophilic Bases

-usually anions that are very sterically hindered (very large) and prevent them from attacking as nucleophiles

-participate only in E2 eliminations

Strong, Non-Nucleophilic Bases

Tert-butyl Lithium : tBuLi

Strong, Non-Nucleophilic Bases

PotassiumTert-butoxide : KOtBu

Strong, Non-Nucleophilic Bases

Lithium Diisopropylamide : LDA

Non-Nucleophilic Bases

H:⁻

Non-Nucleophilic Bases

DBN

Non-Nucleophilic Bases

DBU

Nucleophile Only

halides (Cl⁻, Br⁻, I⁻) ex. LiBr, KI, NaCl

Strong Base/Strong Nucleophile

any NaO-R

Strong Base/Strong Nucleophile

any R-Li

Strong Base/Strong Nucleophile

NaCN or KCN

Strong Base/Strong Nucleophile

NaOH or KOH

Strong Base/Strong Nucleophile

NaCC-R

Strong Base/Strong Nucleophile

NaNH2

Strong Base/Strong Nucleophile

NaNH-R,

Strong Base/Strong Nucleophile

MeO⁻, EtO⁻, HO⁻

Strong Base/Strong Nucleophile

NaN-R₂

Weak Base/Weak Nucleophile

H₂O

Weak Base/Weak Nucleophile

R-OH

strong nuc

H₂S

strong nuc

R-SH