Final Exam Flashcards
How are compounds named
Named according to the number of carbon atoms linked together in the longest chain of carbons
What forms the root name
The number of carbons in the longest continuous chain
How is a simple non branched Alkane named?
Named by the root (number of carbons) followed by the suffix “ane”
How do you name branched Alkanes?
- Find the longest continuous chain of carbons - gives the root name
- Name the branch group using the root name for the number of carbons - To indicate that it is an “yl”
- The compound can be named by putting the three parts of the name together
(Branch + Root + Family)
The number for the location must be added at the beginning
What do you do if there is more than one branch in an Alkane?
- Longest chain forms the root name of the main chain
- The branches are named according to the number of carbons
- The chains are numbered to give the lowest possible number combination for the branches
- Name the branches in alphabetical order
What is there is more than one branch with the same number of carbons?
The terms di, tri are incorporated into the name followed by the position of each group
What happens when a branch within a branch cannot be avoided?
- Label the branch according to the longest continuous carbon chain
- Label the branch off this as normal
- To avoid getting confused with the number of locates associated with the main chain it should be placed in brackets
How do you name cycloalkanes?
- Named by the number of carbons in the ring followed by the prefix cyclo
- If the ring is the longest chain of carbons this is the root name
- if the ring is not the longest carbon chain the ring is treated as a branch
What is a bicyclicalkane?
Have two rings sharing only one carbon are known as spiro compounds
How do you name a Spiro compound?
- The prefix Spiro is added to the name
2. The root name is taken form the total number of carbons in both ring
How do you distinguish between different Spiro carbons with the same total number of carbons but a different number in each ring?
The numbers in each ring (excluding the central carbon) is placed in square brackets with a dot between them
The numbers always go low to high
How do you name a Spiro carbon if there are substitutes on the ring?
When there are substitutes in the ring you start the numbering in the small ring next to the ring junction then in to the larger ring
Go in the direction that will give the lowest number in each ring
What is a bridgehead compound?
When two rings have two carbons in common. Carbons are known as bridgeheads.
How do you name the bridgehead compounds?
- The compounds are given the prefix bicyclo.
- The root name is based on the total number of carbons in the bicycle
- The stereo chemistry is described in brackets
The three numbers depict the number of intervening carbons between the two bridgehead carbons ( in decreasing order)
How do you number the carbons of the bridgehead rings?
- Start with one of the bridgehead carbons and label it
- Proceed around the longest chain of carbons to the second bridgehead
- Number the second bridgehead carbon and continue around the next longest chains of carbons back towards the first bridgehead carbon
- Pass over the first bridgehead carbon (as it is already labelled 1 ) along the final, shortest chain of carbons to the second bridgehead.
How do you name the bridgehead compound when there are substitutes
- Name the branch and add
- yl to the end - Number the substitute according to the number carbon it is attached to
What is difference when naming alkanes, alkenes and alkynes
They are named in similar ways except the a in “ane” is replaced by “e” for alkenes and by “y” for alkynes
How do you show the position of the double or triple bonds?
The position is denoted by a number ( The number carbon that the double is on)
What happens if there is more than one double or triple bond?
If more than one double or triple bond is present then the compound is named using di- or tri-
What happens is the double or triple bond is not part of the longest carbon chain?
A change is made to the standard IUPAC rules
The whole double or triple bond must be in the chain used for the root name even if it is not the longest chain
What are the three possible structural isomers substitutions called?
Ortho
Meta
Para
What is the Ortho- substitution?
The substitutes are at carbons 1 and 2
What is the Meta- substitution?
The substitutes are at carbons 1 and 3
What is the para- substitution?
The substitutes are at carbons 1 and 4
What is the general rule for naming functional groups?
If there is a functional group present which can be named as a suffix then there must be a suffix in the name.
If several functional groups are present the higher priority group will be the suffix the others are added as prefixes.
One exception is the suffixes -ane -ene and -yne can have another suffix denoting another functional group added to the.
- Just remove the terminal e
What is an ether?
Two chains of carbons on either side of an oxygen atom
How do you name the either?
- The longest carbon chain gives you the root name
- The smaller carbon chain is named as alkoxy
- the “alk” describes the number of carbons in the shortest chain
What is an Ester?
Have two carbon chains separated by an oxygen
How is an ester named?
Both chains must be named separately in the full ester name
- Takes the form alkyl alkanoate
What part is the Alkyl when naming an ester?
Name derived from the carbon chain directly attached to the oxygen
What part is the Alkanoate when naming an ester?
Name derived from the carbon chain containing the carbonyl group (C=O)
What is the suffix for a carboxylic acid?
- oic acid
What is important about carboxylic acids?
It is the highest priority functional group
How do you identify the carboxylic
Identified by the COOH group