Chapter 1: Nomenclature Flashcards
5 steps of IUPAC naming:
- identify the parent chain
- number the parent chain
- name the substituents
- number the substituents
- complete the name
Rules for choosing parent chain
most number of carbons
if tie: choose chain with MORE substituents
Rules for numbering the IUPAC parent chain:
always number the chain so that the highest-priority functional group has the lowest possible number
if all substituents have the same priority, number so that they have the lowest possible numbers
how is priority determined
the higher the atomic number, the higher the priority
How are numbers separated from each other and from words in a compound’s names?
numbers are separated by commas (no spaces)
numbers are separated from words within the compound by hyphens (-)
ex. 3,4-dipropryl-1,3-hexadien-5-yne
How are substituents ordered in an IUPAC name?
alphabetical order
do NOT include hyphenated prefixes (di-, tri-, tetra-, n-, tert-) while alphabetizing
DO include non-hyphenated prefixes (iso-, neo-, cyclo-) while alphabetizing
hydrocarbons
compounds that contain only carbon and hydrogen atoms
Carbon chains w/ single bonds only
alkanes
carbon chains w/ double bonds
alkenes
carbon chains w/ triple bonds
alkynes
Names the first 10 alkanes in order (1-10):
methane, ethane, propane, butane, pentane
hexane, heptane, octane, nonane, decane
What is the functional group of an alcohol?
-OH
(hydroxyl)
What is the suffix for an alcohol?
- ol
ex. ethanol
Diol
alcohols with 2 hydroxyl groups
geminal diols
diols with the two OH groups on the same carbon
(rare - they spontaneously lose a water molecule)
vicinal diols
diols with OH groups on adjacent carbons
a common name for ethanol:
ethyl alcohol
a common name for 2-propanol
isopropyl alcohol
carbonyl group
a carbon double bonded to an oxygen
aldehydes
the carbonyl is on a terminal carbon that is also attached to a hydrogen
aldehyde suffix
- al
ex. butanal
methanal common name + structure
formaldehyde
ethanal common name + structure
acetaldehyde
propanal common name + structure
propionaldehyde
ketones
have a carbonyl group somewhere in the middle of the carbon chain
the smallest ketone
acetone
acetone IUPAC name
2-propanone
alpha carbon
the alpha carbon is the carbon adjacent to the carbonyl carbon
carboxylic acid
contain both a carbonyl group and a hydroxyl group on a terminal carbon
methanoic acid common name + structure
formic acid
ethanoic acid common name + structure
acetic acid
propanoic acid common name + structure
propionic acid
alkoxy group
esters
the -OH group of a carboxylic acid is replaced with an alkoxy group (-OR); R is a hydrocarbon chain
ester nomenclature
the first term is the alkyl name of the added R group
the second term is the name of the (original) parent chain with -oate replacing -oic acid
amides
the -OH of a carboxylic acid is replaced by an amino group (any Nitrogen containing group)
amide nomenclature
substituents attached to the nitrogen atom are prefixes labelled with N- (not numbered)
anhydrides
form from 2 carboxylic acid molecules
1 water molecule is removed
many are cyclic
anhydride nomenclature
-oic anhydride
if formed from 2 of the same carboxylic acids: the “acid” is replaced with “anhydride”
if formed from 2 different carboxylic acids: both carboxylic acids are named (without “acid”) and anhydride is added to the end
