a Nucleophilic , Nucleophilic center .Nucleophilic center center 9 ：⊙ Fig.1.Examples of nucleophiles;(a)hydroxide ion;(b)carboxylate ion. Electrophilic Electrophilic a) center b) Electrophilic center H Fig.2. Examples of electrophiles:(a)carbocation;(b)allylic cation. a 0 b) Me2N C-H Me- Me Fig.3.(a)Dimethylformamide (DMF):(b)dimethylsulfoxide (DMSO). College of Science