Flashcards in Organic Chemistry- Nomenclature Deck (90)
What does IUPAC stand for?
International Union of Pure and Applied Chemistry
What is the primary goal of IUPAC?
To create an unambiguous relationship between the name and structure of a compound.
What does IUPAC establish?
No distinct compounds have the same name
what does IUPAC help to do?
Simplifies chemical naming.
what is the parent chain?
The longest carbon chain containing the highest-order functional group
What does the parent chain help to determine?
The root of the name
What must be considered when identifying the highest-order functional group?
If there are double or triple bonds between carbons, they must be considered when identifying the highest functional group.
What provides the suffix when naming a complex?
The highest-priority functional group (with the most oxidized carbon)
Which carbon chain would you use for the suffix if there were two of equal length?
The more substituted chain gets priority
What are the naming steps?
1. Identify the longest carbon chain containing the highest-order functional group.
2. Number the chain
3. Name the substituents
4. Assign a number to each substituent
5. Complete the name
How do you number a carbon chain?
The carbon numbered 1 will be the one closest to the highest-priority functional group. If the functional groups all have the same priority, numbering the chain should make the numbers of the substituted carbons as low as possible.
What should be kept in mind when numbering carbon chains?
The more oxidized the carbon is, the higher priority it has in the molecule
Oxidation state increases with what?
More bonds to heteroatoms
What are Heteroatoms?
Atoms besides carbon and hydrogen, like oxygen, nitrogen, phosphorus, or halogens.
Oxidation state decreases with what?
More bonds to hydrogen
How are rings numbered?
Starting at the point of greatest substitution continuing in the direction that gives the lowest numbers to the highest-priority functional groups.
When numbering a chain, what happens if there is a tie between assigning priority in a molecule with double and triple bonds?
If there is a tie, the double bond takes priority
What are substituents?
Functional groups that are not part of the parent chain
When naming a compound, where will a substituent's name be placed?
At the beginning of the compound name as a prefix, followed by the name of the longest chain.
What should be remembered, when choosing the suffix?
Only the highest-priority functional group will determine the suffix for the compound and must be part of the parent chain.
How are carbon chain substituents named? With what suffix?
Named like alkanes, with the suffix -yl replacing -ane
what does the prefix n- indicate?
This is "normal," in other words, a straight-chain alkane.
Will the n- prefix always be present?
No, assume alkane substituents are normal unless specified.
What do you write if there are multiple substituents of the same type, when naming?
Use the prefix di- , tri-, and tetra- .
These prefixes are included directly before the substituent's name.
When assigning a number to the substituents, what do you do?
Pair the substituents that you have already named to the corresponding numbers in the parent chain.
When assigning number to the substituents, what happens if there are multiple substituents of the same type?
They will get di-, tri- or tetra- prefixes and also a carbon number designation
How do you complete the naming of a compound?
Names begin with the names of the substituents in alphabetical order, with each substituent preceeded by it number. Then, the numbers are separated from each other with commas, and from words with hyphens. Finally finish the name with the backbone chain, including the suffix for the functional group of highest-priority.
when completing the naming of a compound, what are ignored while alphabetizing?
The prefixes like di-, tri-, and tetra,
Also hyphenated prefixes like n- and tert- (or t-)
What are included while computing the naming of a compound and alphabetizing?
Nonhyphenated roots that are part of the name, like iso-, neo-, or cyclo-.
What are hydrocarbons?
Compounds that contain only carbon and hydrogen atoms.
What are alcohols?
Molecules that contain at least one -OH group
What does a -OH group lend to alcohols?
What are alkanes?
Simple hydrocarbon molecules with the formula
What are the names of the 1st four alkane compounds?
Methane (one carbon)
Ethane (two carbon)
Propane (three carbons)
Butane (four carbons)
What is the naming pattern for alkanes with more than four carbons?
The name is the greek root describing the number of carbons followed by -ane
What are the Greek roots from 5-12?
What are common substituents on alkanes?
How are alkyle halides indicated?
By a prefix
What does the MCAT not explicitly test, but, might be seen?
Reactions of alkenes or alkynes, but you may still see the suffixes -ene and -yne, which signify double and triple bonds.
For Alkenes and alkynes, what should be kept in mind?
Many of these compounds will also have common names, and these common names should be known.
On test day, how are you most likely to encounter Alkenes and akynes and their double bonds?
In the context of unsaturated fatty acids or other biochemical compounds
For alkenes and alkynes, how are they named?
The double or triple bond is named like a substituent and is indicated by the lower-numbered carbon involved in the bond. The number may precede the molecule name, as in 2-butene, or it may be placed near the suffix, as in but-2-ene. both are correct. If there are multiple multiple bonds, the numbering is generally separated from the suffix, as in 1,3-butadiene
How are Alcohols named?
By replacing -e in the name of the corresponding alkane with -ol
How are alcohol chains numbered?
The carbon attached to the hydroxyl group (-OH) gets the lowest possible number- even when there is a multiple bonds present.
Why does the hydroxyl group take precedence over multiple bonds?
the higher oxidation state of the carbon
What happens if the alcohol is not the highest-priority functional group?
Then it is named as a hydroxyl substituent (hydroxy-)
How are alcohols often referred to by?
Their common names
If alcohols are written by their common name, what does it look like?
The name of the alkyl group is followed by the word alcohol. Example ethyl alcohol (rather than ethanol) and isopropyl alcohol (rather than 2-propanol
What are alcohols with two hydroxyl groups called? How are they indicated?
Diols or glycols and are indicated with the suffix -diol. The entire hydrocarbon name is preserved, and -diol is added.
When naming diols, what must one do?
Must number each hydroxyl group. For example. ethane-1,2-diol is an ethane molecule that has a hydroxyl group on each carbon.
What is the common name of ethane-1,2-diol?
What are geminal diols?
Diols with hydroxyl groups on the same carbon
What are vicinal diols?
Diols with hydroxyl groups on adjacent carbons
What's another name for geminal diol?
Why are geminal diols not commonly seen?
They spontaneously dehydrate (lose a water molecule0 to produce carbonyl compound with functional group C=O
Aldehydes and ketones are two classes of molecules that contain what?
Carbonyl groups, which is a carbon double-bonded to an oxygen.
How do aldehydes and ketones differ?
In the placement of the carbonyl group:
Aldehydes are chain-terminating
Ketones are found in the middle of the carbon chain.
What does chain-terminating mean?
They appear at the end of a parent chain
Aldehydes and ketones do not have what? They are only connected to what?
Leaving groups connected to the carbonyl chain
They are only connected to alkyl chains or in the case of aldhydes, hydrogenn atoms
Which molecules have leaving groups?
Carboxylic acids and their derivatives connected to their carbonyl carbon.
Aldehydes have what?
A Carbonyl group found at the end of the carbon chain.
Because _______ is a terminal functional group, it ________ and ________.
Because the carbonyl group in Aldehydes is a terminal functional group, it takes precedence over many others, it is generally attached to carbon number 1.
How are Aldehydes named?
By replacing the -e of the parent alkane with the suffix -al. When the aldehyde is at position 1, we do not need to include this number in the chemical name.
Methanol, ethonal, propanal, are almost exclusively referred to how? When compounded with Aldehydes?
By their common name
They are called: Formaldehyde, Acetaldehyde, and Propionaldehyde
Because ketones contain a carbonyl group in the middle of the carbon chain, what must be done?
We always have to assign a number to the carbonyl carbon when naming ketones (except proponone, which must have the ketone on carbon 2.
How are ketones named?
Replacing the -ane, in the paret alkane with the suffix -one. Just when naming other compounds, be sure to give the carbonyl the lowest possible number if it is the highest-prority group.
How are ketones commonly named?
By listing the alkyl groups in alphabetical order, followed by ketone
What is the smallest possible ketone molecule?
What is special about acetone?
It defies traditional naming conventions because it has three rather than two carbons (acet-, like eth- generally refers to two carbons).
In a more complex molecule, where carbonyl isn't the highest priority, how do aldehyde and ketone names change?
The aldehydes and ketones are named as substituents, using the prefix oxo-. This is in reference to the carbonyl oxygen and applies for both ketones and aldehydes. Sometimes ketones may also be indicated with the prefix keto-
What is another convention that may be seen on the MCAT when maing carbons relative to the carbonyl group?
The carbon adjacent to the carbonyl carbon is indicated by alpha. Moving away from the carbonyl, the succesive carbons are referred to as beta, gamma, and delta carbons. This applies on both sides of the carbonyl in the same fashion, so the carbons on both sides of a ketone are considered alpha carbons.
What are carboxylic acids?
Contain both a carbonyl group (C=O) and a hydroxyl group (-OH) on a terminal carbon
Carboxylic acid groups have their associated carbon numbered what?
What is the most oxidized functional group on the MCAT?
Three bonds to carbon
Only carbon dioxide with four bonds to carbon contains a more oxidized carbon.
Carboxylic acids are what? And other groups are what?
The highest-priority functional group in MCAT-tested nomenclature.
All other groups are named as substituents using prefixes.
How are carboxylic acids named?
By replacing -e in the name of the parent alkane with the suffix -oic acid.
What are the common names for Methanoic acid, Ethanoic acid, and Propanoic acid?
What are the carboxylic acid derivatives?
The final category of functional groups and include
What are esters?
The hydroxyl group (-OH) is replaced with an alkoxy group (-OR, where R is a hydrocarbon chain).
How are esters named?
Ester naming is based on the naming conventions for carboxylic acids, The first term is the alkyl name of the esterifying group, Think of this first term as an adjective describing the ester, based on the identity of the alkyl (R) group. The second term is the name of the parent acid, with -oate replacing the -oic acid suffix.
What is an example of ester compound naming?
Methanoic acid (formic acid) would form butyl methanoate with exposure to butanol under appropriate reaction conditions.
What are Amides?
The hydroxyl group is replaced by amino group (nitrogen-containing group)
Why are amide compounds more complex?
The amino nitrogen can be bonded to zero, one or two alkyl groups.
How are amides named?
Similar to esters, except that the suffix become -amide
How are subtituents attached to the nitrogen labeled in amides?
Labeled with N-, incidcating that this group is bonded to the parent molecule via a nitrogen. These substituents are included as prefixes in the compound name and are not numbered.
What are anydrides?
The formation of anydride from two carboxylic acid molecules, one water molecule is removed.
Many anhydrides are what? Which results from what?
Cyclic, which may result from the intramolecular dehydration of a dicarboxylic acid.
How are anhydrides named?
Replacing acid with anhydride in the name of the corresponding carboxylic acid if the anhydride is formed from ony two carboxylic acid. If the anhydride is not symettrical, both carboxylic acids are named (without the suffix acid) before anhydride is added to the name.
What are the functional groups in order from highest-priority to least?
Alkene (Tied with alkyne, except in cyclic compounds)
Alkyne (Tied with alkene)