How are alkenes used in the synthesis of other organic compounds?

Alkenes are used in the synthesis of other organic compounds through reactions such as addition, polymerisation, and oxidation.

Alkenes are unsaturated hydrocarbons that contain a carbon-carbon double bond. This double bond is highly reactive, making alkenes very useful in the synthesis of other organic compounds. The double bond can be broken and new atoms or groups of atoms can be added in a process known as addition reactions. For example, when bromine water is added to an alkene, it turns colourless as the bromine atoms add across the double bond, forming a dibromo compound.

Another important reaction of alkenes is polymerisation. In this process, many small molecules (monomers) join together to form a large molecule (polymer). This is how plastics are made. For instance, ethene can be polymerised to form polyethene, a common plastic. The double bond in the alkene molecule breaks and forms single bonds with other ethene molecules, creating a long chain polymer.

Alkenes can also undergo oxidation reactions. In the presence of a suitable catalyst, alkenes can be oxidised to form alcohols, ketones, or carboxylic acids. For example, ethene can be oxidised to form ethanol, a type of alcohol. This reaction is particularly important in the industrial production of alcohols.

In summary, the reactivity of the carbon-carbon double bond in alkenes makes them versatile in the synthesis of a wide range of other organic compounds. Through addition reactions, polymerisation, and oxidation, alkenes can be transformed into many different types of compounds, including halogenated compounds, polymers, and oxidised products.