It is difficult to type these but I'll do my best. This is the first question and I just don't get it. My professor is out of the country so any help would be appreciated.
Give the IUPAC name for each of the following alkanes:
CH3
I
a. CH3--CH--CH2--CH2--CH3
b. CH3 CH3
CH3--CH--CH--CH3
c. CH3 CH3
CH3--CH2--CH--CH2--CH--CH3
d. CH2--CH3
CH3--CH2--CH--CH--CH2--CH3
I
CH2--CH3
It is difficult to handle spacing on the board; it ignores any spaces after the first one. Try drawing condensed structures for these.
For example, propane is
CH3CH2CH3 and 2-methyl propane would be
CH3CH(CH3)CH3
In general, find the longest chain that includes the most triple/double bonds and name that as the base, then add the groups to that base name.
Ans b-hecsane ans c-octane
To determine the IUPAC name for each of the given alkanes, we need to follow a set of naming rules called IUPAC (International Union of Pure and Applied Chemistry) nomenclature.
Let's break down the naming process for each of the alkanes:
a. CH3--CH--CH2--CH2--CH3
Count the number of carbon atoms in the main chain: 5 carbon atoms.
Since it is a continuous chain, we use the prefix "pent" to indicate 5 carbons.
The suffix "-ane" is used to indicate that the compound is an alkane.
Therefore, the IUPAC name for a. is pentane.
b. CH3 CH3
CH3--CH--CH--CH3
In this case, we have a branched alkane. Identify the longest continuous carbon chain, which contains 4 carbon atoms. So, we use the prefix "but-" to indicate 4 carbons.
There is a methyl group (CH3) attached to the second carbon atom. We indicate this substituent as "2-methyl-".
The suffix "-ane" is added to indicate it is an alkane.
Therefore, the IUPAC name for b. is 2-methylbutane.
c. CH3 CH3
CH3--CH2--CH--CH2--CH--CH3
Identify the longest continuous carbon chain: 6 carbon atoms. So, we use the prefix "hex-" to indicate 6 carbons.
There are two substituents on the main chain: one methyl group (CH3) attached to the second carbon atom, and one ethyl group (CH2CH3) attached to the fourth carbon atom. We indicate these as "2-methyl-" and "4-ethyl-".
Combine the prefix(es) and substituent name(s) with the suffix "-ane" to form the complete IUPAC name.
Therefore, the IUPAC name for c. is 2-methyl-4-ethylhexane.
d. CH2--CH3
CH3--CH2--CH--CH--CH2--CH3
I
CH2--CH3
Identify the longest continuous carbon chain: 6 carbon atoms. So, we use the prefix "hex-" to indicate 6 carbons.
There is a propyl group (CH2CH2CH3) attached to the third carbon atom. We indicate this substituent as "3-propyl-".
There is one iodine atom (I) attached to the fourth carbon atom. We indicate this substituent as "4-iodo-".
Combine the prefix(es) and substituent name(s) with the suffix "-ane" to form the complete IUPAC name.
Therefore, the IUPAC name for d. is 3-propyl-4-iodohexane.
Remember, while writing IUPAC names, it is essential to accurately identify and number the substituents on the main carbon chain. Also, maintain proper alphabetical order when listing multiple substituents.