What do the numbers in compound names like 1,4-diaminobenzene mean?

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What do the numbers in compound names like 1,4-diaminobenzene mean?

In: Chemistry

3 Answers

Anonymous 0 Comments

Chemical names are often instructons on how to draw a molecule. The numbers tell you on which position (carbon atom) atoms or groups of atoms are attached to.

In your example, there are 6 carbon atoms forming a hexagon. 1,4 means that the next group (here the *amino* group consisting of one nitrogen and two hydrogens) is not at the next carbon(that would be 1,2) , not at the one after that either(that would be 1,3) , but on the one after after that.

So it looks like this: [https://en.wikipedia.org/wiki/P-Phenylenediamine](https://en.wikipedia.org/wiki/P-Phenylenediamine)

Anonymous 0 Comments

The carbon atoms in the benzene molecule are typically numbered. 1,4 refers to which carbon atom in the benzene molecule the amine group is attached to. Di-amino means 2 amine molecules (Di being the prefix for 2). Therefore, we have an amino group attached to the 1 carbon atom of the benzene molecule and another amino group attached to the 4 carbon atom of the benzene molecule. I think that’s correct. Been a while since I touched organic chemistry.

Anonymous 0 Comments

The numbers indicate the positions of the amino groups on the arene (benzene group). The arene has the shape of a hexagon, the counting starts at the top and continues in a clockwise direction.

The compound you named is also called para-diaminobenzene, “para” meaning parallel to. In this case it means that one amino group is on the exact opposite from the other group.