BR M102 hapter 16 otes lass otes Page 1 of 7 hapter 16 Amines Amines derivatives of ammonia R 2 primary amine 3 R 1 R 2 secondary amine 3 R 1 R 2 R 3 tertiary amine 3 * Remember that classification of amines as 1, 2, and 3 are different from alcohols. alcohols: 2 1 2 3 amines: 2 2 1 2 3 * Amines are classified as: aliphatic amines aromatic amines only alkyl groups are attached to the nitrogen one or more aryl groups are present (benzene-like or benzene containing) * heterocyclic amines the nitrogen atom is part of a ring. If the ring is saturated, then it is called a heterocyclic aliphatic amine. If the ring is part of an aromatic ring, then it is called a heterocyclic aromatic amine. aming 1. Simple 1 amines are named by naming the single alkyl group attached to the nitrogen and adding the suffix amine. 2 Methylamine 2 Isopropylamine
BR M102 hapter 16 otes lass otes Page 2 of 7 2. omplicated 1 amines are named by naming the alkane and calling the 2 an amino group. Precedence is equal to halogens. Br 2 3 amino 2 bromocyclopentanol 3. For 2 amines, the two alkyl groups are named in alphabetical order followed by the suffix amine. If the two alkyl groups are the same, the prefix di is used. 2 Dimethylamine Ethylisopropylamine Diphenylamine 4. 3 amines are named similarly to 2 amines. Use di for 2 identical groups and tri for 3 identical groups. 3 2 2 2 Triethylamine 2 2 Benzylethylmethylamine 5. When one R group is aromatic, the amine is generally named as a derivative of aniline. The capital letter is used to show that the alkyl group or groups are attached to nitrogen. 2 2 Br 23 aniline methylaniline meta bromo, diethylaniline
BR M102 hapter 16 otes lass otes Page 3 of 7 Amphetamines also called pep pills are powerful stimulants of the central nervous system (S) they raise the level of glucose in the blood. Amphetamines are used to: 1. counter depression 2. reduce hyperactivity in children 3. depress appetite Problems with amphetamines is that they: 1. are addictive 2. can lead to sleeplessness 3. can cause unhealthy weight loss 4. can cause paranoia Amphetamines are similar to the natural hormone adrenalin 2 Amphetamine 2 adrenalin, a 2 amine 1 amine 2 Methamphetamine 2 amine 2 Alkaloids * Alkaloids are weak basic organic compounds obtained from green plants. * All alkaloids are amines. * Alkaloids are named by either (1) the plant they came from, (2) the effect they produce, or (3) who discovered them. All of the names end in ine. oniine found in emlock plant, the poison which killed Socrates. 2 2
BR M102 hapter 16 otes lass otes Page 4 of 7 icotine the active ingredient in tobacco in small doses it is a stimulant, but in large doses it is a poison it is used commercially as an insecticide it is addictive caffeine the stimulant in tea and coffee it is mildly addictive 3 3 atropine the poison found in belladonna in small doses it will dilate the pupils Roman women used it for this purpose 2 3 morphine one of a number of alkaloids found in opium from poppy plants it is a powerful painkiller called a narcotic it is highly addictive heroin made from morphine and not found in nature even more highly addictive and illegal codeine also found in opium used in some cough suppressants 3 addictive cocaine produced in the leaves of the South American coca plant a local anesthetic and a stimulant addictive
BR M102 hapter 16 otes lass otes Page 5 of 7 strychnine highly toxic used as a rat poison quinine found in the bark of the cinchona tree in Peru used as a cure for malaria Physical Properties of Amines 1. A 1 or 2 amine molecule can form a hydrogen bond with another molecule of itself. These are weaker hydrogen bonds than alcohols or water. Therefore their boiling points are lower than alcohols. 2. Amines of up to 2 or 3 carbons are gases at room temperature. 3. Amines of low molecular weight are highly soluble in water. 4. Amines have strong odors like raw fish. An example is putrescine. 2 2 2 2 2 2 Basicity of Amines * Amines are weak bases like ammonia. * Amines act as bases by accepting a proton. R 2 + l -------> + R 3 + l 2 + l -------> + 3 + l methylammonium chloride * All aliphatic amines have similar base strengths slightly stronger than ammonia. * Aliphatic amines are present as ammonium ions in blood to help keep blood p at 7.40. * Aromatic amines are much weaker bases much less than ammonia.
BR M102 hapter 16 otes lass otes Page 6 of 7 * arboxylic acids can react with amines in an acid base reaction 2 2 + -------> + 2 3 + * Amine salts are the ionic compounds produced when amines react with acids they are solids at room temperature they are named by changing the amine ending to ammonium or changing the aniline ending to anilinium and then adding the name of the negative ion. 2 + l -------> + 2 + l Ethylmethylamine ydrochloric acid Ethylmethylammonium chloride * An older system of naming is used in pharmacies. ame the amine followed by the word hydrochloride if the compound is a chloride salt or use bisulfate if it is a hydrogen sulfate salt example: The product above would be called Ethylmethylamine hydrochloride and written as: 2 l ot the correct structural formula! * The structure of amines depends on p. An amine can exist in water only at high p. An amine salt can exist only at low p. The conversion to and from amine to amine salt is easy. * early all amine salts are soluble in water. * Drugs are usually in the form of amine salts the amine itself is called the free base. itrites in Meat * Sodium nitrite, a 2, is added to some meat as a preservative to inhibit bacterial growth. This prevents botulism and helps to keep red meat from turning brown. * a 2 reacts with amines to produce carcinogens, called -nitrosoamines or -nitrosamines. R R + 2 -------> R R amine nitrite -nitrosoamine + 2
BR M102 hapter 16 otes lass otes Page 7 of 7 * Stomach acid converts a 2 to 2. * 2 can react with amines in the intestines to produce the carcinogen. Tranquilizers * Tranquilizers are drugs which provide relief from the symptoms of anxiety or tension. * The first modern tranquilizers were derivatives of benzodiazepine * In 1960, Librium was introduced. * The most widely used tranquilizer is diazepam, or also called Valium. benzodiazepine * Tranquilizers act as sedatives they diminish activity and excitement in the central nervous system to produce drowsiness and sleep. ommon eterocyclic Amines heterocyclic aliphatic amines pyrrolidine piperidine heterocyclic aromatic amines pyridine pyrimidine purine building blocks for the amine bases of DA and RA