Untitled - Kelly Walsh High School

308 CHEMISTRY FOR THE UTTERLY CONFUSED
Don’t Forget!
taking the name of the alkane that contains the same number of carbon
atoms, dropping the -ane ending and adding -yl. Methane would then
become methyl; propane becomes propyl, and so on. If there is more than
one branch, list them alphabetically.
3. A location number is necessary to indicate the point of attachment of a particular
substituent. We assign these numbers by consecutively numbering
the carbons of the base hydrocarbon starting at one end of the hydrocarbon
chain. Choose the end so that there will be the lowest sum of location numbers
for the substituent groups. Place this location number in front of the
substituent name and separate it from the name by a hyphen (i.e., 2-methyl).
4. Place the substituent names with their location numbers in front of the base
name of the alkane in alphabetical order. If there are identical substituents
(e.g., 2 methyl groups), then give the location numbers of each, separated by
commas using the common Greek prefixes (such as, di-, tri-, and tetra-.) to
indicate the number of identical substituent groups (i.e., 2,3-dimethyl). Do
not use these Greek prefixes in the alphabetical arrangement.
5. The last substituent group becomes a part of the base name as a prefix.
Compounds that have the same molecular formulas, but different structural formulas,
are isomers. When dealing with hydrocarbons, this amounts to a different
arrangement of the carbon atoms. Isomers such as these are structural isomers.
In writing structural isomers as well as any organic compound, remember that
carbon forms four bonds!! One of the most common mistakes that a chemistry
student makes is writing an organic structure with a carbon atom having less or
more than four bonds.
Name the following compound:
CH 3
CH 3 C CH 2 CH 2 CH CH 2 CH 3
CH 3
CH 2
CH 2 CH 2 CH 3