Name the following three compounds according to the IUPAC system:
1. CH3-CHCH3-CHCH3-CH2-CH2-CH2-CH3
2. CH3-CH2-C(CH3)2-CH2-CHCH3-CH2-CH3
3. CH3-CH2-C(CH3)2-CHCH3-CH2-CH2-CH3
I'm not sure how to do these :| It would be appreciated if someone could tell me HOW to name these using the IUPAC system?
1. CH3-CHCH3-CHCH3-CH2-CH2-CH2-CH3
2. CH3-CH2-C(CH3)2-CH2-CHCH3-CH2-CH3
3. CH3-CH2-C(CH3)2-CHCH3-CH2-CH2-CH3
I'm not sure how to do these :| It would be appreciated if someone could tell me HOW to name these using the IUPAC system?
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The parent compound will be the carbon chain with the largest number of atoms.
CH3CH(CH3)CH(CH3)(CH2)3CH3 has an unbroken chain of 7 carbon atoms.
CH3 = first carbon (1 atom)
(CH2)3 = next 3 carbons (3 atoms)
CH(CH3) = a carbon in the chain with a methyl group (1 atom)
CH(CH3) = another carbon in the chain with a methyl group (1 atom)
CH3 = the last carbon atom (1 atom)
1 + 3 + 1 + 1 + 1 = 7 carbon atoms
Now some latin. Any alkane (single bonded hydrocarbon) larger than butane has some sort of latin name referring the number of carbon atoms. "Penta" is "5" and pentane contains 5 atoms. "Hepta" is "7" so the parent compound is "Heptane"
The side chains are also named after the alkanes they resemble in terms of their number of atoms. CH3 is a methyl group because methane has a single carbon atom. The position of the groups is made by assigning consecutive integers to the main chain. I don't think it is really important which end of the molecule one begins. If one began on the left, the first compound would be
2,3-dimethyl heptane
Going right to left, the name becomes
5,6-dimethyl heptane
and of course there is another rule which can be applied.
CH3CH(CH3) is an iso group, meaning it is isometric or symmetrical. If a carbon atom has a pair of side chains of equal length and they are at the end of the main chain, the compound can be referred to in terms of the iso group. The group itself is named according to the number of carbon atoms. The dimethyl grouop has 3 carbons, so it is an isopropyl group. This is why isopropyl alcohol is (CH3)2CHOH. The name of the compound would then be based on the fact an isopropyl group subtracts 2 carbon atoms from the main chain. This would make the first compound
1-isopropyl, 2-methyl pentane
or
5-isopropyl, 4-methyl pentane
I think standard practice is to assign positions to side branches with the lowest possible numbers so the two suitable answers for the first compound would be
2,3-dimethyl heptane
or
1-isopropyl, 2-methyl pentane
The other formulas are named using the same rules presented. A C(CH3)2 group is a "dimethyl group". The other latin/english terms for carbon chains are:
C = methyl
C2 = ethyl
C3 = propyl
C4 = butyl
C5 = pentyl
C6 = hexyl
C7 = heptyl
C8 = octyl
C9 = nonyl
C10 = decyl
To name the parent chain, they "yl" suffix is substituted with "ane"
CH3CH(CH3)CH(CH3)(CH2)3CH3 has an unbroken chain of 7 carbon atoms.
CH3 = first carbon (1 atom)
(CH2)3 = next 3 carbons (3 atoms)
CH(CH3) = a carbon in the chain with a methyl group (1 atom)
CH(CH3) = another carbon in the chain with a methyl group (1 atom)
CH3 = the last carbon atom (1 atom)
1 + 3 + 1 + 1 + 1 = 7 carbon atoms
Now some latin. Any alkane (single bonded hydrocarbon) larger than butane has some sort of latin name referring the number of carbon atoms. "Penta" is "5" and pentane contains 5 atoms. "Hepta" is "7" so the parent compound is "Heptane"
The side chains are also named after the alkanes they resemble in terms of their number of atoms. CH3 is a methyl group because methane has a single carbon atom. The position of the groups is made by assigning consecutive integers to the main chain. I don't think it is really important which end of the molecule one begins. If one began on the left, the first compound would be
2,3-dimethyl heptane
Going right to left, the name becomes
5,6-dimethyl heptane
and of course there is another rule which can be applied.
CH3CH(CH3) is an iso group, meaning it is isometric or symmetrical. If a carbon atom has a pair of side chains of equal length and they are at the end of the main chain, the compound can be referred to in terms of the iso group. The group itself is named according to the number of carbon atoms. The dimethyl grouop has 3 carbons, so it is an isopropyl group. This is why isopropyl alcohol is (CH3)2CHOH. The name of the compound would then be based on the fact an isopropyl group subtracts 2 carbon atoms from the main chain. This would make the first compound
1-isopropyl, 2-methyl pentane
or
5-isopropyl, 4-methyl pentane
I think standard practice is to assign positions to side branches with the lowest possible numbers so the two suitable answers for the first compound would be
2,3-dimethyl heptane
or
1-isopropyl, 2-methyl pentane
The other formulas are named using the same rules presented. A C(CH3)2 group is a "dimethyl group". The other latin/english terms for carbon chains are:
C = methyl
C2 = ethyl
C3 = propyl
C4 = butyl
C5 = pentyl
C6 = hexyl
C7 = heptyl
C8 = octyl
C9 = nonyl
C10 = decyl
To name the parent chain, they "yl" suffix is substituted with "ane"