Introduction to Haloalkanes and Haloarenes

Haloalkanes and Haloarenes

• Haloalkanes and haloarenes are a class of organic compounds that contain halogen atoms.

Nomenclature and Structure

• Haloalkanes are named by replacing the suffix "-ane" in the parent alkane with "-halo" (e.g., chloromethane).
• Haloarenes are named by adding the prefix "halo-" to the parent arene (e.g., chlorobenzene).

Methods of Preparation

• Halogenation of alkanes: reaction of alkanes with halogens (Cl2, Br2, I2) to form haloalkanes.
• Free radical halogenation: reaction of alkanes with halogens in the presence of UV light.
• Halogenation of alkenes: reaction of alkenes with halogens to form haloalkanes.

Physical Properties

• Boiling points: increase with increasing molecular weight and decreasing polarity.
• Melting points: increase with increasing molecular weight and symmetry.
• Solubility: haloalkanes are generally insoluble in water but soluble in organic solvents.
• Density: typically higher than that of water.

Chemical Reactions of Haloalkanes

• Nucleophilic substitution: reaction with nucleophiles (e.g., OH-, CN-) to form substituted compounds.
• Elimination reactions: reaction with strong bases to form alkenes.
• Reaction with metals: reaction with metals (e.g., Na, Zn) to form organometallic compounds.

Chemical Reactions of Haloarenes

• Electrophilic aromatic substitution: reaction with electrophiles (e.g., NO2+, Cl+) to form substituted arenes.
• Nucleophilic aromatic substitution: reaction with nucleophiles (e.g., OH-, CN-) to form substituted arenes.
• Sandmeyer reactions: reaction with copper(I) salts and amines to form diazonium salts.

Uses of Haloalkanes and Haloarenes

• Intermediates in organic synthesis.
• Pharmaceuticals: used as anesthetics and in the production of pharmaceuticals.
• Pesticides: used as insecticides and herbicides.
• Solvents: used as solvents in various industrial applications.

Learn about the nomenclature, structure, and general properties of haloalkanes and haloarenes. Explore methods of preparation including halogenation of alkanes, free radical halogenation, and halogenation of alkenes. Understand physical properties such as boiling points, melting points, solubility, and density. Dive into chemical reactions including nucleophilic substitution, elimination reactions, and reactions with metals for haloalkanes and electrophilic aromatic substitution and nucleophilic aromatic substitution for haloarenes.