Let's see if we can handle some
slightly more difficult amine naming examples. So if we look at this blue
molecule right here, we always want to start off by finding
the longest carbon chain. It looks like it's this chain
at the bottom where we have one, two, three, four, five,
six, seven, eight carbons. So it's going to be octan. We don't want to just call it
octane because we have these functional groups up here, and
maybe one of them's going to take higher priority
than just the fact that this is an alkane. And, in fact, one
of them will. So let's look at them. So over here we an
amino group. That would make this
molecule an amine. So this is an amino
group right here. Then we have this
benzene ring. And when benzene is a functional
group, we call it a phenyl group. And that's derived from I think
it's either the Greek or the Latin word for light because
benzene was first isolated from, I guess, the
air around lanterns or something, so this is called
a phenyl group. And then finally we have this
OH, which would make this whole thing an alcohol, or we
could call that a hydroxy group, so this right here
is a hydroxy group. Now, this is just something
that you need to know. There's no way to kind
of deduce it. The people who've decided how
to name things just decided that certain groups take higher
priority over others. And out of these three groups,
the hydroxy group, the thing that's making this whole thing
an alcohol, takes the highest priority, so this is what's
going to define the suffix. So if we start numbering, we
want to start numbering this chain closest to the highest
priority group. So we'll start numbering
at this end. So it's one, two, three, four,
five, six, seven, eight. So we have a hydroxy group on
the three carbon, so this is octan-3-ol. If this was not a high priority,
we would put a hydroxy in the front, but since
this is the highest prioritiy, its defining this
as an alcohol, octanol. But we put the 3 there to say
it's on the three carbon. And then, of course, this
would be 5-phenyl. This right here is 5-phenyl. And this right here
is 8-amino. And amino comes before phenyl in
alphabetical order, so this whole molecule is going to
be-- let me write it over here-- it's going to be
8-amino-5-phenyl-octan-3-ol. And we're done. So this is an aromatic compound
because of the benzene ring. It's an amine because
of the amino group. And it's an alcohol because
of the hydroxy group. Now let's look at this molecule
here in green. And actually, I forgot
to draw part of it. This is supposed to
be a benzene ring. So let me make clear. That is a benzene ring. So let's think about
the different functional groups here. And we'll start with the one
that you've probably never seen before. This is a nitro group, and
it's highly explosive. Maybe in a future video, I'll
show you some nitroglycerin and some TNT, as you know, which
are highly explosive, but they have nitro
groups on them. So this right here
is a nitro group. It takes very low precedence in
the whole scheme of things. So this will never be the cause
of naming the suffix. We just know that this is a
nitro group right here. We, of course, have
a bromo group that we've seen many times. That is a bromo group. And then we have an amino
group right here. So this is going to be--
let me do this in a different color. This is definitely an amine. This is an amino group
right there. And out of these three groups,
the amino group is definitely of the highest priority. So you might be tempted to name
this 1-amino-2,3-brom o-4-nitrobenzene, but when a
benzene ring is attached to an amino group, this one also has
one of those special names. And let me just do it on
the side right here. So if I just have a benzene
ring attached to an amino group, so that's an NH2 right
there, we call this molecule right here, and this is just
the common name for it and it's something to put in your
toolkit, this is aniline. So that will be the base name. This whole thing right
here we call aniline. Let me write it over here. So this is aniline. And then we always want to start
numbering at the group that's really defining the
molecules, so we start numbering here. And you want to go in the order
where you're going to bump into something first. So,
one, two, three, four. So this is going to be-- if we
look at them, and bromo comes alphabetically before nitro,
so it's going to be 3-bromo-4-nitroaniline. And we are done!