HALOALKANES AND HALOARENES
Introduction
Halo alkanes are the compounds containing halogen atom attached to the sp3 hybridized carbon atom of an alkyl group.
Haloarenes are the compounds containing halogen atom attached to sp2 hybridized carbon atom of an aryl group.
Classification of halo alkanes and halo arenes On the Basis of number of halogen atoms
Depending on number of halogen atoms present in halo alkanes and halo arenes they can be classified as mono (one atom), di (two atoms), or Polyhalogen (tri- (three atoms), tetra- (four atoms), etc.) compounds.
Classification of halo alkanes and halo arenes on the basis of compounds containing sp3C—X Bond
(a) Alkyl halides or halo alkanes (R—X)
They create a homologous series represented by CnH2n+1X and can be further classified as primary, secondary or tertiary.
(b) Allylic halides
The compounds with halogen atoms bonded to sp3-hybridised carbon to carbon-carbon double bond (C=C) i.e. to an allylic carbon.
(c) Benzylic halides
The halogen atom of these compounds is bonded to sp3-hybridised carbon atom placed next to an aromatic ring.
Classification of halo alkanes and halo arenes on the basis of compounds containing sp2 c—x bond
· Vinylic halides
The halogen atom of these compounds is bonded to sp2-hybridised carbon atom of a carbon-carbon double bond (C = C).
(b) Aryl halides
The halogen atom of these compounds is bonded to the sp2-hybridised carbon atom of an aromatic ring.
