Electrophiles: The name electrophiles means electron loving. Electrophiles are electron deficient. They may be positive ions or neutral molecules.
Ex: H
+, Cl
+, Br
+, NO
2+, R
3C
+, RN
2+, AlCl
3, BF
3 Nucleophiles: The name nucleophiles means ‘nucleus loving’ and indicates that it attacks the region of low electron density (positive centres) in a substrate molecule. They are electron rich they may be negative ions or neutral molecules.
Ex: Cl- Br-, CN-, OH-, RCR2-, NH3, RNH2, H2O, ROH etc.