3.11 Amines

• A means is a compound where the hydrogen's on ammonia are replaced with alkyl groups.
• The naming of a means is derived from ammonia, where ammonia is represented as NH3.
• A primary amine has one methyl group attached.
• A secondary amine has two methyl groups attached.
• A tertiary amine has three methyl groups attached.
• Another way to make a primary amine is by reducing nitriles using a nickel catalyst and hydrogen gas.
• Reducing nitriles using a strong reducing agent such as lithium aluminium hydride and dilute acid is more expensive than using hydrogen and nickel catalyst.
• The reaction involves reacting a nitrile with a reducing agent, forming a primary amine.
• The number in front of the primary amine represents the number of hydrogen atoms needed to balance the molecule.
• Unlike using halogen or alkane, the only products produced using this method are primary amines.
• The cheapest way to make primary amines in industry is to reduce nitriles using hydrogen gas and nickel or a platinum catalyst, a reaction called catalytic hydrogenation.
• The overall reaction involves reacting a nitrile with hydrogen gas, forming a primary amine.
• Primary amines are made by reacting methyl amine with chloro ethane, forming a secondary amine.
• A quaternary amine has four methyl groups attached.
• Chloroethane is a halogen of alkane and ammonia is a primary amine.
• Using two amines instead of two ammonia molecules can produce a pure primary amine.
• The mechanism produces primary, secondary, tertiary, and quaternary salts, making it unsuitable for producing a pure primary amine.
• The electrons in the ammonia molecule go towards the Delta positive carbon, breaking the bond on the chlorine, forming an intermediate with the ammonium ion and two nh3.
• Another ammonia molecule reacts with the hydrogen, acting as a base, nucleophile, and accepting a proton, forming a primary amine and a chlorine that has found a new home with an ammonium molecule.
• If the goal is to produce a primary amine, a different mechanism should be used.
• Aromatic amines withdraw electrons from the groups that are attached to them, making the lone pair of electrons less available and therefore weakening the base.
• Aliphatic amines can also act as nucleophiles in their reactions.
• The strength of a base is dependent on the availability of lone pair of electrons on the nitrogen.
• The type of group bonded to the nitrogen determines the availability of these electrons and therefore the strength of the base.
• Aromatic amines are the weakest type of bases, followed by ammonia, primary aliphatic amines, and then primary aliphatic amines are the strongest bases.
• Aromatic amines are also nucleophiles, as they themselves have a lone pair of electrons.
• Primary aliphatic amines are electron pushing groups, pushing electrons from this side towards the nitrogen, increasing the electron density at this site and making these electrons more readily available, resulting in a stronger base.
• The more available these lone pair of electrons are, the stronger the base will be.
• A means, with a lone pair of electrons that allows them to accept a proton and hence act as a base, are mainly used as bases.
• A means have a covalent or coordinate bond with both electrons in the bond originating from the lone pair in the nitrogen.
• Oil and water are immiscible, meaning they do not mix at all.
• Cationic surfactants are used in shampoo as they have a positive ammonia mine which is attracted to negatively charged fibers in the hair, removing static and used in hair conditioner and fabric softener.
• Oil is suspended on plates and washing up liquid is added, causing the oil to run into the water.
• Bits of oil collect in blobs on the top of the water, mixed in amongst the bubbles in the solution.
• Cationic surfactants, with a nonpolar tail attracted to the oil and grease, and a polar head group attracted to water, trap the oil between them, allowing the oil and water to mix.
• Quaternary ammonium salts have a long hydrocarbon tail and are known as cationic surfactants.
• Aliphatic amines are used in everyday life as surfactants, which have the ability to clean things.
• The structure of cationic surfactants consists of a hydrocarbon tail and an ionic head group, which has a significant impact on how they work.
• Tertiary hydrogens have been displaced or swapped for an alkyl group, resulting in a positive charge on the nitrogen atom in the middle.
• In a washing up liquid, the hydrocarbon tail of a cationic surfactant is attracted to oil, while the ionic head group is attracted to water, resulting in the separation of oil and water.