Organic Chemistry Functional isomers (sometimes
~ The study of the structure, properties, composition, referred to as functional group
reactions, and preparation of carbon-containing isomers)
compounds. b) Steriochemical isomerism (sterioisomers)
~ Most organic compounds contain carbon and hydrogen, molecules have the same connectivity,
but they may also include any number of other elements except for the arrangement of those bonds
(e.g., nitrogen, oxygen, halogens, phosphorus, silicon, in 2D or 3D space
sulfur). Types:
Enantiomers (mirror images) -
Exceptions: nonsuperimposable mirror
Carbon compounds such as images
Carbides: silicon carbide [SiC2), Diastereomers (not mirror
Carbonates: calcium carbonate (CaCO3), images)-nonsuperimposable
Cyanides: sodium cyanide (NaCN), non-mirror images
Graphite (C),
Carbon dioxide (CO2), Shorcuts for Computation of Isomers
Carbon monoxide (CO)
Alkanes 2n-4 + 1
Nature of Organic Compounds Alkenes 2n-2 + 1 (Even)
1. Organic compounds are compounds of Carbon Alkenes 2n-2 (Odd)
almost always bonded to another carbon and/or Alkynes 2n – (2n-1) (Even)
hydrogen. Alkynes 2n – 2n (Odd)
Alcohols 2n-2
Alkyl Halides 2n-2
3. Organic compounds are largely composed of covalent
compounds, that generally have low melting points
and has a limited solubility with water
Properties of Carbon that allows it to form millions of
compounds: Solubility rules:
Catenation - The property of carbon element In general, an increase in molecular weight leads
capable of forming long carbon chains. Carbon to an increase in intermolecular forces in a solid
atoms have the possibility to link with one and decreased solubility.
another through covalent bonds to form chains Compounds having branched chain is more
and rings. soluble than the corresponding straight-chain
a) Carbon can link to each other to form linear, compound
branched or cyclic hydrocarbons. Branching lowers intermolecular forces
Tetravalency - Carbon has a valence number of and decreases intermolecular attraction.
four therefore it is capable of bonding with four The position of the functional group in the
other atoms of carbon or atoms of some other carbon chain also affects the solubility.
mono-valent element.
Carbon atoms can form single, double and triple Chemical Bonds
bonds. ~ Refers to the formation of a chemical bond between two
Carbon atom can bond with many other atom, H, or more atoms, molecules or ions
N, O, P, S, F, Cl, Br, and I ~ Forces that hold atoms together
~ Attaining the Octet Rule ((noble gas configuration)
2. Organic molecules exhibit isomerism. ~ Types: Ionic, covalent
~ Can be explained by valence bond theory
Isomerism - is a phenomenon by which more Valence Bond Theory
than one compounds have the same chemical ~ Describes a covalent bond as the overlap of half-
formula but different chemical structures. filled atomic orbitals (each containing a single
Two types: Structural and steriochemical electron) that yield a pair of electrons shared
a) Structural or constitutional isomerism between the two bonded atoms.
are specific types of isomers that share the ~ Each of the bonded atoms maintains its own
same molecular formula but have different atomic orbitals but both atoms share the electron
bonding atomic organization and bonding pair in the overlapping orbitals
patterns. ~ The greater the extent of overlap , the stronger
Types: the bond
Skeletal isomers (commonly ~ The covalent bond can also be formed by overlap of an
referred to as chain isomers) atomic orbital having 2 electrons with an empty orbital of
Positional isomers (also known another atom in which case it is called coordinate covalent
as regioisomers) bond