Reactive Intermediates
A molecule or ion or an atom which has life time appreciably longer than the molecular vibration and that is formed directly or indirectly from the reactants and convert into the product is termed as reactive intermediates. The reactive intermediate is in the depth of energy well of a reaction and it is sufficiently enough to prevent any molecular vibration along the reaction coordinate to convert back to the reactant or to proceed to form product itself.
That mean, the reactive intermediate possess some stability and also they are very reactive
Examples for the reactive intermediates in organic reactions
1. Carbocations
2. Carboanions
4. Carbenes
5. Benzynes
Common features of reactive intermediates
a. They forms in low concentration
b. Usually having unusual valance stage
c. Highly reactive
d. Have some stability through resonance
e. Formation can be monitored using spectroscopic measurement
In order to generate reactive intermediates in multi-step reactions, bond breaking of the reactants is necessary as mentioned previously.
There are two possible ways of bond breaking:
i. Homolysis
ii. Heterolysis
Homolysis
A bond breaks the way that each fragment gets an electron. Free radical intermediates are formed using homolysis.
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| Homolysis |
Heterolysis
A bond electrons remain with one fragment during the bond cleavage. Heterolysis produces ionic intermediates.
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| Heterolysis |