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organic chemistry nomenclature Cheat Sheet (DRAFT) by

overview of organic chemistry nomenclature (gr12 level)

This is a draft cheat sheet. It is a work in progress and is not finished yet.

PREFIXES (based on # of carbon)

# of carbons
root name
substi­tuent group prefix
1
meth-
methyl-
2
eth-
ethyl-
3
prop-
propyl
4
but-
butyl-
5
pent-
pentyl-
6
hex-
hexyl-
benzene
benzene
phenyl-
7
hept-
heptyl-
8
oct-
octyl-
9
non-
nonyl-
10
dec-
decyl-
suffix following root name depends on the classi­fic­ation of the molecule it is referring to. words following substi­tuent group prefix depends on its placement during the name; either followed by the root name or a "­-" (e.g. 2-ethy­l-4­-me­thy­lpe­ntane).

benzene is included because it is quirky and special and unique.

ADDITIONAL PREFIXES

classi­fic­ation
identi­fic­ation
prefix
cyclic hydroc­arbons
carbons are organized in ring formation
cyclo-
multiple groups
2 of the same group exists
di-
 
3 of the same group
tri-
 
4 of the same group
tetra-
 

SUFFIXES

group name
identi­fic­ation
suffix
alkane
only single carbon bonds
-ane
alkene
at least one double carbon bond
-ene
alkyne
at least one triple carbon bond
-yne
alcohol
hydroxyl at the end of chain
-ol
carboxylic acid
COOH group at the end of chain
-oic acid
aldehyde
oxygen is double bonded to a carbon at the end of a chain
-al
ketone
oxygen is double bonded to a carbon in the middle of a chain
-one
ester
O=C-O-R; carboxylic acid + alcohol
-oate
ether
R-O-R
-oxy-
amine
nitrogen bonded to up to three carbon groups
-amine
amide
O=CH-N
-amide
note: list does not go in order of naming priority; R represents any carbon group

tip for memori­zation: several of the groups have the ending in their name (indicated in bold in the first column).
  

HYDROC­ARBON NAMING E.G.

1. identify longest chain with highest priority group included as root (e.g. cycloh­exane)
2. number carbons in accordance with sub. group priority (e.g. propyl is sub. group with the highest priority, start there)
3. identify substi­tuent groups (e.g. propyl on carbon 1, methyl on carbon 3)
4. write full name with substi­tuent groups in alphab­etical order (e.g. 3-meth­yl-­1-p­rop­ylc­ycl­ohe­xane)

ALDEHYDE NAMING E.G.

1. confirm aldehyde presence (i.e. double bonded oxygen at the end of a chain)
2. count longest chain with aldehyde included (consi­dering that no other functional groups of a higher priority are present)
3. begin counting from aldehyde
4. identify sub. groups (i.e. two methyls on carbon 3)
5. write full naming with ending "­-al­" (e.g. 3,3-di­met­hyl­oct­anal)

KETONE NAMING E.G.

1. identify ketone presence (i.e. double bonded oxygen anywhere in the middle of the chain)
2. count longest root with the ketone (consi­dering that there are no other functional groups of higher priority present)
3. number carbons, giving the ketone priority, taking note of what number it falls on (e.g. carbon 2)
4. identify sub. groups (e.g. fluorine on carbon 4)
5. write full name with ending "­-on­e" (e.g. 4-fluo­roh­ept­an-­2-one)

ESTER NAMING E.G.

1. begin with the carbon chain attached to the single bonded oxygen (i.e. the alcohol side), identi­fying its longest chain; name like sub. group (e.g. phenyl).
2. identify the longest chain on the other side of the molecule (i.e. the acid side), identi­fying its longest chain starting from the carbon that is double bonded to the oxygen (e.g. pentane).
3. identify any sub. groups and number accord­ingly (e.g. none)
4. write full name with ending "­-oa­te" (e.g. phenyl pentan­oate)