HYDROCARBONS: NOMENCLATURE Flashcards
Composed wholly or especially coined or selected syllables
Systematic Name
Refers to the structure of compounds
Systematic Name
IUPAC Meaning
The International Union of Pure and Applied Chemistry
A name no part of which is used in a systematic sense
Trivial Name
Refers to compounds independent of structure and sometimes given before the structure is known
Trivial Name
A name of which only a part is used in a systematic sense
Semisystematic-Semitrivial Name
Under Organic Compounds
• Open-Chain / Aliphatic
• Closed Chain / Cyclic
Under Closed Chain / Cyclic
• Homocyclic / Carbocyclic
• Heterocyclic
Under Homocyclic / Carbocyclic
• Alicyclic
• Aromatic
All organic compounds may be divided into two broad classes based upon the pattern of chain of carbon atoms.
• Open-chain or Aliphatic compounds
• Closed-chain or Cyclic compounde
This class includes all hydrocarbons (saturated and unsaturated) and their derivatives which have open-chain structures.
Aliphatic Hydrocarbons
Those which contain single bonds between all carbon atoms.
Saturated hydrocarbons
On the other hand, unsaturated compounds contain a double (-C = C-) or a triple (-C = C-) bond between two carbon atoms.
Aliphatic Hydrocarbons
These compounds have at least one ring (cyclic) system. These are further divided into two sub- classes: homocyclic and heterocyclic based on the atoms present in the ring. They are called homocyclic or carbocyclic when the ring is formed by carbon atoms only.
Cyclic Hydrocarbons
Homocyclic (carbocyclic) compounds may again be divided into two groups namely :
• Alicyclic compounds
• Aromatic compounds
This group includes saturated and I unsaturated cyclic hydrocarbons which resemble with the aliphatic hydrocarbons in properties.
Alicyclic Hydrocarbons
The group of homocyclic compounds having special set of properties. They also have characteristic smell or aroma and hence called _______.
These include aromatic hydrocarbons and their derivatives are examples of such compounds.
Aromatic
Alkanes Formula :
CnH2n+2
Alkenes formula :
CnH2n
Alkynes formula :
CnH2n-2
In order to bring uniformity and rationality in naming the organic compounds throughout the world, International Union of Chemistry (in 1958) came out with a system of nomenclature later known as ?
IUPAC (International Union of Pure and Applied Chemistry) system.
IUPAC was by
International Union of Chemistry (1958)
The purpose of the IUPAC system of nomenclature is to establish an ____________ of naming compounds to facilitate communication.
international standard
The goal of the system is to give each structure a unique and unambigous name, and to complete each name with a unique and unambigous structure.
IUPAC’s goal
IUPAC nomenclature is based on naming molecule’s ___________________ connected by single bonds either in chain or in ring.
longest chain of carbons
Multiple bonds other than C and H, are indicated by ________ or ________ according to specific set of priorities.
prefixes or suffixes
It indicates the number of carbon atoms in the longest possible continuous carbon chain also known as parent chain chosen by a set of rules. This is used for different length of carbon chain are shown below.
Root word
It is used to indicate the degree of saturation or unsaturation in the main chain. It is added immediately after the root word.
Primary suffix
It is used to indicate the main functional group in the organic compound and is added immediately after the 1º suffix.
Secondary suffix
Denotes the numeral or letter that indicates the position of an atom or group in a molecule.
Locant
Numerals is a locant when it indicates the position of a _________ or bond in a structure
substituents
- separated by commas (e.g. 1,2,5,6-tetrabromocyclohexane), no space after the comma or colon
- sets of numerals are joined by hyphen arranged in ascending order
Numerals
Place as early in a name as to not cause confusion
Locant
In branched chain hydrocarbons, one or more _____ groups are present as side chain attached to the main straight chain of carbon atoms.
alkyl groups
The carbon atoms of the side chain constitute ______ groups.
alkyl groups
The carbon atoms of the side chain constitute ______ groups.
alkyl groups
These alkyl groups are written as ________ in the IUPAC name.
prefixes
An alkyl group is obtained from an alkane by ________ one hydrogen atom.
removing
Since the general formula of alkane is CnH2n+2, the general formula of alkyl group is _________.
CnH2n+1
The ____________ are generally represented by R- and named by replacing the suffix -ane of the corresponding alkane by-yl.
alkyl groups
Denotes number and identify attached groups.
Locant / Prefix
Longest carbon chain
Root
Functional class
Suffix / Ending
