ABSTRACT
Carbocations are alkyl ions containing one trivalent, positively charged carbon atom and they are the intermediate of electrophilic addition to alkenes. Carbocations are electrophiles whose electrophilic center is the trivalent carbon atom. Primary carbocations tend to rearrange to secondary or tertiary carbocation or tend to form a multicenter bonding. Alkyl group is a hydrocarbon fragment which is bonded to a hydrocarbon chain or an electrophilic/nucleophilic center. The inductive effect decreases exponentially as the distance between the substituent and electrophilic/nucleophilic site increases. The alkyl group has ambiguous behavior as substituent group, that is, it can be moderate electron withdrawing group or moderate electron donating group by inductive effect depending on the electron deficiency or electron accumulation of the electrophilic site or the nucleophilic site, respectively. The identification of carbonium and carbenium ions can be done experimentally or theoretically.
