Halocarbons, Alcohols and Ethers

Addition Reactions: reaction in which two molecules of reactant combine to form a single product.  The general formula for an addition reaction is:

Types of Addition Reactions

        Halogenation: X-Y = some diatomic molecule.

        Hydrohalogenation: X-Y= a hydrogen halide molecule, for example: HBr or HCl.                  When the alkene reacting with the hydrogen halide is more complex than ethene, two                 different structural isomers will will be formed.)                

Substitution Reactions: one atom or group is replaced by another.

        Aromatic Substitution: Benzene rings resist addition reactions, but will, in the                                 presence of a         catalyst and at high temp and pressure, undergo substitution reactions.  A                 ring hydrogen will be replaced by another group.

Reduction Reaction: a loss of oxygen, a gain of hydrogen or a gain of electrons by a substance.

        Hydrogenation: X-Y = diatomic hydrogen (H₂).  Usually requires a catalyst.  This is a                 reduction reaction.  (reduces an alkene to an alkane).

Elimination Reactions: these are the reverse of addition reactions.  One molecule becomes 2 products.  The general formula is:

Types of Elimination Reactions:

        Dehydrohalogenation:  X-Y = a hydrogen halide

        Dehydration: The elimination of water.

        Dehalogenation:  X-Y = a diatomic halogen

Alcohols: compounds in which one H of the water molecule is replaced by a hydrocarbon chain or ring, so the general formula of an alcohol is ROH.  The functinal group of alchols is -OH (the hydroxyl group).  

        To name alcohols: drop the -e ending of the parent alkane and add the ending -ol.  The parent chain includes the carbon attached to the hydroxyl group.  Give the hydroxyl group the lowest possible number.  Use diol, triol, and tetrol to name alcohols with more than one hydroxyl group.

        Properties of alcohols: Alcohols are capable of intermolecular hydrogen bonding, and because of this they have a higher boiling point than the alkanes, alkenes and alkynes.  The alcohol is made up of a nonpolar and hydrophobic carbon chain, and the hydroxyl group.  Alcohols with small C chains are extremely soluble in water, but larger C chains make the alcohol insoluble.