Lesson 1 introduction to organic Compounds
By the end of the lesson, you will be able to
Rationale
Organic chemistry is used in many aspects of everyday life. For example, it is essential in the production of pharmaceuticals, plastics, textiles, and food additives. Organic chemistry also plays a central role in understanding and developing products such as fuels, detergents, and cosmetics. Additionally, it is crucial in the study of biochemistry, which helps us understand processes in living organisms. From the food we eat to the medicines we take, organic chemistry has a significant impact on our daily lives
Keywords;
Organic chemistry is the study of carbon compounds
The word “organic” was originally used
by eighteenth-century chemists to describe substances obtained from living sources—plants
and animals. These chemists believed that nature possessed a certain vital force and that only
living things could produce organic compounds. This romantic notion was disproved in 1828 by
Friedrich Wohler, a German chemist who prepared urea, an organic compound, from the reaction
between inorganic compounds lead cyanate and aqueous ammonia:
Activity
Write the electronic configuration of carbon
what can you say about the electronic configuration concerning, the group, the periodm, the number of shell.
Functional Group
A functional group is a group of atoms or bond that is largely responsible for the
chemical behavior of the parent molecule.
Hydrocarbons are compounds made up of Caarbon and Hydrogen atoms only.
Carbon can form more compounds than any other element because carbon atoms are
able not only to form single, double, and triple carbon-carbon bonds, but also to link up
with each other in chains and ring structure
Hydrocarbon; is a compound containing carbon and hydrogen only.
Saturated hydrocarbons; Are organic compounds containing carbon – carbon single bonds only.
Unsaturated Hydrocarbons; Are organic compounds which contain carbon – carbon double or triple bonds.
Functional Group; is an atom or group of atoms or a bond in an organic compound that gives the molecule its characteristic chemical properties.
Cracking; is the breakdown of complex or large molecules of hydrocarbons by action of heat or a catalyst to produce small molecules.
Polymerization; is the combination of small organic molecules (monomers) to form large molecules (polymers)
Saponification; is a reaction between fats or oil and hot concentrated alkali to form soap and glycerol.
Ester ; an Ester is an organic compound produced by the reaction between an organic acid or alkanoic acid and an alcohol or alkanol.
Isomerism; is the occurrence of compounds of the same molecular formular but different structural formular.
Detergent; they are cleaning agents
Or they are substances that have cleaning power and can remove dirt from objects or substances].
Plastics; are polymers of hydrocarbons which can be molded into shapes.
Fats ; are solid esters or lipids obtained from the reaction between glycerol and long chain fatty acids.
Organic compounds ;Organic compounds can be defined as compounds which contain hydrocarbon.
Sources of Organic compounds
- Petroleum (Crude Oil)
2. Natural Gas
3. Coal From plants and Animals
Examples of natural organic compounds
1. Carbohydrates
2. Protein
3. Vitamins
4. Enzymes
5. Hormones
6. Herbs
7. Fats and oils
Examples of artificial organic compounds
1. Plastic
2. Insecticides
3. Pesticides
4. Soap
5. Dyes
6. Drugs etc.
Types of organic compounds
i. Hydrocarbons
ii. Alkanol
iii. Alkanoic acids
iv. Alkanoates
v. Fats and oils.
Hydrocarbons Hydrocarbons are organic compounds, composed entirely of carbon and hydrogen.
Alkanes – They have single Bonds
Alkenes – they have double bond
Alkynes They have triple Bonds
Aromatic Hydrocarbons – Ring compounds
Classes of Organic Compounds
On the basis of structure, hydrocarbons are divided into two main classes—
aliphatic and aromatic.
Aliphatic hydrocarbons do not contain the benzene group, or the benzene ring, whereas aromatic
hydrocarbons contain one or more benzene rings.
What are Cycloalkanes?
Different organic molecules of organic compounds have different properties based upon their structure such as the Cycloalkanes. Did you know about the body fat present in the human body and also some food and hair products are made up of these hydrocarbons? Hence, these organic compounds exist in all the day-to-day examples of life.
Cycloalkanes are the class of hydrocarbons having a ring-like structure. This ring is formed due to their saturated nature, and they have three compounds of alkane present in the structure which helps them in forming a ring. They have the general formula CnH2n ,Where n is said to be the number of carbon atoms present in the organic compound.
These consist of carbon-hydrogen bonds and also carbon to carbon single bonds where these carbon atoms join forming a ring or in the shape of a cyclic structure. Cyclopropane is considered to be one of the smallest cycloalkanes, and most of this class of members are said to be more stable in nature.
Some common examples of cycloalkanes are the cyclopentane, Cyclobutane, cyclohexane, and cycloheptane, cyclooctane, etc as shown below in the image. The number of carbon atoms present in the compound decides the structure of cycloalkane. For example, the saturated hydrocarbon with 4 numbers of carbon atoms is named Cyclobutane whereas the hydrocarbon with three carbon atoms present in the structure is given the name Cyclopropane.
Cycloalkanes- Properties
The various physical and chemical properties of Cycloalkanes are given below-
- The first four classes of cycloalkanes are said to be in gaseous state in the room temperature
- These saturated hydrocarbons are said to have their boiling points ranging between 10 – 20 K.
- These compounds are also reported exhibiting higher melting points and densities
- These are also called as saturated hydrocarbons since saturated compounds form ring structure
- Since the electronegativity between the carbon-hydrogen bonds is found to be too less for these compounds, they are said to be not having any polarity between the bonds.
- This class of saturated hydrocarbons is said to be insoluble in water, and the cycloalkanes in liquid form are said to be the good form of solvents for other organic compounds.
- The molecule of cycloalkane gets destroyed when burned
- Cyclopropane is said to be the most reactive compound when compared to other cycloalkanes.
Common Uses
Some uses are given below-
- In the medical applications, cycloalkanes are used as an organic solvent in the production of drugs
- These are utilised in the manufacture of hair products as well as in the food industries
- The cycloalkane called cyclopropane is used as an anaesthetic agent in the medical field
- Carboplatin which is derived from the cyclobutane is used to treat cancers
- They are also employed in the petroleum industries.
- Some classes of cycloalkanes are used for pigmentation purposes and also used as fragrances in the perfume manufacturing sector.
- Some of these saturated hydrocarbons are found in the tissues of plants and animals as steroids.
Frequently Asked Questions – FAQs
What is a Cycloalkane in chemistry?
In organic chemistry, the monocyclic saturated hydrocarbons are cycloalkanes (also called naphthenes, but different from naphthalene). Analogous to their usual alkane equivalents, cycloalkanes have the same carbon count: cyclopropane, cyclobutane, cyclopentane, cyclohexane, etc.
Is benzene a Cycloalkene?
Ringed structures called cyclic hydrocarbons may be formed by hydrocarbons. Since they have the least ring pressure, cyclopentane and cyclohexane are the most popular cycloalkanes. Benzene has a ring of delocalized electrons, which gives the structure extra stability.
How do you count Cycloalkanes?
Cycloalkane numbering a When a cycloalkane’s carbons are counted, begin with a substituted carbon such that the lowest numbers (sum) are available for the substituted carbons. b. Number by alphabetical order, whether two or more related substituents are present.
Why is Benzene not called hexene?
Benzene is a molecule with a ring, but hexene is a chain. Alternative carbons in benzene have double bonds, but only one double bond is found in hexene. The benzene molecular formula is C6H6, but C6H12 is hexene.
Does benzene have double bonds?
We would imagine benzene to have reactions like ethene because of the three double bonds – just more so! Ethene undergoes further reactions in which the electrons are used to bind with additional atoms and one of the two bonds connecting the carbon atoms breaks.
Alkanes
Alkanes have the general formula CnH2n + 2, where n = 1, 2, . . . . The essential characteristic of alkane hydrocarbon molecules is that only single covalent bonds are present.
The alkanes are known as saturated hydrocarbons because they contain the maximum
number of hydrogen atoms that can bond with the number of carbon atoms present.
The simplest alkane (that is, with n = 1) is methane CH4, which is a natural product
of the anaerobic bacterial decomposition of vegetable matter under water. Because it
was first collected in marshes, methane became known as “marsh gas.” A rather improbable but proven source of methane is termites. When these voracious insects consume wood, the microorganisms that inhabit their digestive system break down
cellulose (the major component of wood) into methane, carbon dioxide, and other compounds. An estimated 170 million tons of methane are produced annually by termites!
It is also produced in some sewage treatment processes.
1. The parent name of the hydrocarbon is that given to the longest continuous chain of
carbon atoms in the molecule. Thus, the parent name of the following compound is
heptane because there are seven carbon atoms in the longest chain:
CH3 CH2 CH2 CH CH2 CH2 CH3
1 2 3 4 5 6 7
CH3
2. An alkane less one hydrogen atom is an alkyl group. For example, when a hydrogen atom is removed from methane, we are left with the CH3 fragment,
which is called a methyl group. Similarly, removing a hydrogen atom from the
ethane molecule gives an ethyl group, or C2H5. Table 24.2 lists the names of
several common alkyl groups. Any chain branching off the longest chain is
named as an alkyl group.
3. When one or more hydrogen atoms are replaced by other groups, the name of the
compound must indicate the locations of carbon atoms where replacements are
made. The procedure is to number each carbon atom on the longest chain in the
direction that gives the smaller numbers for the locations of all branches. Consider
the two different systems for the same compound shown here:
2-methylpentane 4-methylpentane
CH3 CH CH2 CH2 CH3 CH3 CH2 CH2 CH CH3
1 3 2 5 4 1 2 3 5 4
CH3 CH3
The compound on the left is numbered correctly because the methyl group is located at carbon 2 of the pentane chain; in the compound on the right, the methyl
group is located at carbon 4. Thus, the name of the compound is 2-methylpentane,
not 4-methylpentane. Note that the branch name and the parent name are written as
a single word, and a hyphen follows the number.
4. When there is more than one alkyl branch of the same kind present, we use a prefix
such as di-, tri-, or tetra- with the name of the alkyl group. Consider the following
examples:
CH3 CH CH CH2 CH2 CH3 CH3 CH2 C CH2 CH2 CH3
CH3
CH3
1 4 2 3 6 5 1 2 3 6 4 5
2,3-dimethylhexane 3,3-dimethylhexane
CH3 CH3
When there are two or more different alkyl groups, the names of the groups are
listed alphabetically. For example,
CH3 CH2 CH CH CH2 CH2 CH3
CH3 C2H5
4-ethyl-3-methylheptane
1 3 2 4 6 5 7
5. Of course, alkanes can have many different types of substituents. Table 24.3 lists
the names of some substituents, including nitro and bromo. Thus, the compound
CH3 CH CH CH2 CH2 CH3
NO2 Br
1 3 2 4 6 5
is called 3-bromo-2-nitrohexane. Note that the substituent groups are listed alphabetically in the name, and the chain is numbered in the direction that gives the lowest number to the first substituted carbon atom.
Addition reaction
3.12: Uses and Sources of Alkanes
