j mcm oc pharmacy fm 1 04

8/7/2019 J McM OC Pharmacy Fm 1 04

http://slidepdf.com/reader/full/j-mcm-oc-pharmacy-fm-1-04 1/28

O r g a n i c C h e m i s t r yO r g a n i c C h e m i s t r y

AminesAmines

LaboratoriumLaboratorium KimiaKimia OrganikOrganik –– JurusanJurusan KimiaKimia

FakultasFakultas MatematikanMatematikan dandan IlmuIlmu PengetahuanPengetahuan AlamAlam

UniversitasUniversitas PadjadjaranPadjadjaran

20092009



Amine

1. What are the different types of amines?Be able to recognize primary, secondary, tertiary, and heterocyclicamines.

2. How are amines named?Be able to name simple aminers and write their structures, given thenames.

3. What are the eneral ro ertie of amine ?

Be able to describe amine properties such as hydrogen bonding,solubility, boiling point, and basicity.

4. How do amines react with water and acids?Be able to predict thestructure of the ammonium ions and of the salts formed by reactionsof amineswith water and acids..

5. What are some natually occuring types of amines and someamine-containing drugs?Be able to describe some types of amines found in biomolecules,plants, and drugs . substitution reactions.



AMINES

Amine are compounds that contain one or more organic groups bonded to

nitrogen: RNH2, R2NH, or R3N.Amine are classified as primary, secondary, or tertiary, depending on how manyorganicsubstituentsarebonded to thenitrogen atom.

Primary Amine, an amine that has one organic group bonded to nitrogen RNH2.

Secondary Amine, an amine that two one organic group bonded to nitrogen R2NH.

Tertiary Amine, an amine that has three organic group bonded to nitrogen R3N.



AMINES

The groups bonded to the amine nitrogen may be alkyl or aryl groups.



NAMING AMINES

Primary alkyl amines, RNH2, are named simply by ientifying the alkyl group

attached to nitrogen and adding the suffix –amine to the alkyl group name.

Secondary and tertiary amines with two or three identical groups are

named by adding the appropiate prefix, di- or tri- , to the alkyl group name



NAMING AMINES

Secondary and tertiary amines with nonidentical R- groups are named as N-

substituted derivatives of a primary amine.

The largest of the organic groups bonded to nitrogen is chosen as the parent

compound, and the other groups are considered N -substituents (N -because

they’r attached directly to nitrogen).

The simplest aromatic amine is known by the commom name anline . When the –NH2

group must be named as a substituent, amino- is used as a prefix



Heterocyclic Nitrogen Compounds

Heterocycle, a ring that contains nitrogen or some other atom in addition to carbon

Heterocyclic nitrogen compounds may be nonaromatic or aromatic.



Heterocyclic Nitrogen Compounds



PROPERTIES OF AMINES

Amine are analogous to amonia in many of their physical properties, just as alcohols

are analogous to water

Like amonia, amines have an unshared electron pair onthe nitrogen atom and have

poar bonds because the nitrogen atom is electronegative.

Amine form hydrogen bonds in the same way that ammonia does and are higher

boiling han alkanes of similar size.




The differences in properties between amines and alcohols are accounted for by

hydrogen bonding.

Because nitrogen atoms are less electronegative than oxygen atoms, they form

weaker hydrogen bonds, and di-, and trimethylamine and ethylamine are gases at

room temperature.

Tertiary amine molecules have no hydrogen atoms attashed to nitrogen and, because

they cannot hydrogen-bond with each other, are lower boiling than either amines or

alcohols of similar molecular weight.

All amine, however, can hydrogen-bond to water molecules throught the lone

electron pair on their nitrogen atoms, as a result, amines with up to about six carbon

atoms are quite soluble in water.




Primary and secondary amines are hydrogen-bonded and

higher boiling than alkanes, but lower boiling point thanalcohols.

Tertiary amine are lower boiling than secondary or primary

amines because hydrogen bonding is not possible.

The simplest amines are gases; other common amines are

liquids.

Volatile amines have unpleasant odors.

Simple amines are water-soluble because of hydrogen

bonding.

Amines are weak Brønsted-Lowry bases.

Many amines are physiologically active, and many are toxic.



BASICITY OF AMINES

Amonia is a weak Brønsted-Lowry base, that is, ammonia can use its lone pair of

electrons to accept a hydrogen ion (proton) from an acid and form the ammonium

ion, NH4+.

The aqueous solution of many amines are basic because of the following

equilibrium:



BASICITY OF AMINES

Amines react with strong acids such as hydrochloric acid to yield ammonium salts

according to the general equation:



BASICITY OF AMINES

The reaction between amines and acids is reversible and can be made to take place

in either direction depending on the reaction conditions.

An amine is protonated to yield an ammonium ion when treated with acid, and anammonium ion is deprotonated to yield a neutral amine when treated with base.

The positive ions formed by protonation of alkylamines are named by replacing the

ending –amine by the ending –ammonium . To name the ions of heterocyclic amines,

the amine name is modified by replacing the –e with –ium .



AMMONIUM SALTS

An amine salt is composed of a cation and an anion and is usually named by

combining the cation and anion names.

(C6H5)CHOCH2CH2N(CH3)2∙Cl or (C6H5)CHOCH2CH2NH+(CH3)2.Cl-

Ammonium salt formation, like carboxylate saltformation, provides a means for

converting an insoluble compound into a water-soluble derivative.



AMMONIUM SALTS

Because many amines are unstable in air, salt formation allows the amine to be

stored in a more stable form.

When the free amine is needed, it is easily regenerated by treatmen with a base:

Ammonium salts can be formed by reaction of an amine with an acid, as shown

CH3NH3+ Cl- (aq ) + NaOH(aq ) CH3NH2(aq ) + NaCl (aq ) + H2O (l )

above, and also by reaction of an alkyl halide with an amine:



AMMONIUM SALTS

The reaction of a tertiary amine with an alkyl halide produces a quaternary

ammonium salt , an ammonium salt with four R groups on the nitrogen atom:



Quaternary ammonium salts have no H atom that can be removed by a base and no

lone pair that can be protonated, so their structure in solution is uneffected by

changes in pH.

One commonly encountered quternary amonium salt has the following structure,

where R reprsents a range of C8 to C18 alkyl groups.

AMMONIUM SALTS



AMINES IN BIOMOLECULES

Protein are polymers of amino acids, which all contain an amino group and a

carboxylic acid group.

A second major class of biomolecules, the nucleotides, all contain nitrogen

heterocyclic rings derived from either purine or pyrimidine. Nitrogen heterocycles

are also part of several vitamins, including the B vitamins:



AMINES IN BIOMOLECULES

Several members of the diverse class of compounds known as neurotransmitters,

which transmit nerve impulses throughout the body, are amines, including serotoninand dophamin.



AMINES IN PLANTS

The roots, leaves, and fruits of flowering plants (angiosperms) are a rich source of

amines, including many thar are physiologically active.These compounds, once called ”vegetable alkali” because their water solution are

basic, are now referred to as alkaloids.

The molecular structures of approximately 5500 alkaloids have been determined.

The potato growns in the absence of sunlight and should also be stored awy from

sunlight, which causes formation of poisonous solanine (along with green

chlorophyl) under the skin.



AMINES IN PLANTS

Coniine is extracted

from poison hemlock

(Conium maculatum )

Atropine is the toxic substance in the herb

known as deadly nightshade or belladonna

(Atropa belladonna ).



AMINES IN PLANTS

Poppy,

“Papaver somniferum ”

Morphine and Codeine was the first pure compound

to be isolated from the poppy (Papaver somniferum ).

Heroin, another close

relative of morphine, does

not occur naturally but is

easily synthesize in chemical

laboratory.



AMINES IN DRUGS

Given the variety of nitrogen-containing compounds that are physiologically active,

it’s not surprising that many drugs are amines or nitrogen heterocycles.

The relationship between molecular structure and physiological activity is the key tounderstanding drug action and to discovering new drugs.

Histamin is the biomolecules responsible for symptoms of allergic reaction familiar

to hay fever sufferers.

It’s also the chemial that causes an itchy bump when an insect bites you.

The antihistamines are a family of drugs than counteract histamine, and members of

this family have in common a disubstituted ethylene side chain, usually with two N -methyl groups.

The mosquito injects antigen,

substances that triger a response by

the body’s immune system.

The immune system in turn triggers

release of histamine, which causesswelling, itchiness, and redness

around the bite.



AMINES IN DRUGS

Neurotranmitters and Drugs that Mimic Their Action (Sympathomimetics)

Dopamine is a precursor of norepinephrine, a principal messenger in the nervous

system.

Epinephrine (adrenaline) is the compound specifically responsible for causing the

surge of energy we feel in a frightening situation.

Ephedrine and its salts are used in over-the counter medications for atshma and

nasal congestion because they dilate bronchial and nasal passageways.



AMINES IN DRUGS

Neurotranmitters and Drugs that Mimic Their Action (Sympathomimetics)

Isoproterenol is a presciption drug for bronchial asthma.

Amphetamine is the parent compound of a family of central-nervous system

stimulant that produce an array of effects like those of epinephrine, including

excitment, increased blood pressure, quickened reflexes, and appetite suppression.



AMINES IN DRUGS

Demerol (Meperidine) is widely used as a painkiller

Methadone is used in the tritment of heroin addiction.

j mcm oc pharmacy fm 1 04

Documents