Alkyl Halide/ Halo Alkane

Alkyl halide/ Halo alkane Organic Chemistry I

Properties • Electronegativity of atoms generally increases going from left to right in a row and from bottom to top in a column in the periodic table. Fluorine is the most electronegative element. The halogens are more electronegative than carbon and halogen-carbon bonds are polar covalent bonds with a partial positive charge on the carbon atom and a partial negative charge on the halogen atom. • The carbon atom in carbon-halogen bonds is therefore susceptible to attack by nucleophiles. When a nucleophile attacks and becomes bonded to the carbon atom of an alkyl halide, the carbon-halogen bond is broken. • In these reactions the halogen is called the leaving group (even though it is an atom). The symbol X is often used to represent any halogen atom.

Structure of Alkyl Halide

PHYSICAL PROPERTIES ALKYL HALIDES: INTERMOLECULAR FORCES • Boiling Point. When describing the effect of alkane structure on boiling point, we pointed out that the forces of attraction between neutral molecules are of three types listed here. The first two of these involve induced dipoles and are often referred to as dispersion forces, or London forces. • 1. Induced-dipole/induced-dipole forces • 2. Dipole/induced-dipole forces • 3. Dipole–dipole forces