Electrophile & nucleophile/unit-12

Electrophile:

A reagent which can accept an electron pair in a reaction is called electrophile. Electrophiles are electrons deficient and can accept a pair of electrons. Electrophile may be positively charged or neutral species. These are also called electron loving (philic) or electron seeking species (E⁺). For example,

H⁺, H₃O⁺, Cl⁺, CH₃⁺, NO₂⁺ (Positively charged)

AlCl₃, BF₃, SO₃ (Neutral)

Nucleophiles:

A reagent which can donate an electron pair in a reaction is called nucleophile. A nucleophile is electron rich and seeks electron deficient sites, i.e., nucleus loving or nucleus seeking (Nu^–). According to Lewis concept, nucleophiles behave as Lewis bases. For example,

X ^–, ^–OH, CN^–, RCOO^– (Negatively charged)

NH₃, R₃N, H₂O, ROH, ROR (Neutral molecules)