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Naming Ethers - IUPAC Nomenclature With Branching, Organic Chemistry Practice Problems



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in this video we're going to focus on

naming ethers we're going to talk about

the common names and also the IU pack

moves so let's start with this example

let's say if we have ch3 Oh ch2 ch3 what

is the common name of this particular

ether so notice that we have a methyl

group on the left and on the right we

have an ethyl group if you recall

methylene is associated with one carbon

ethylene is for two carbons propane is

for three butane is four pentane is five

hexane is six heptane is seven octane is

eight nine is nine decades ten so we

have two carbons on the right so it's an

ethyl group one on the left methyl and

to put it together we need to

alphabetize it so it's called ethyl

methyl ether this is the common name now

what about the IU PAP name what is it

for this particular example

well let's redraw it so the longest

structure or the longest chain is the

two carbons on the left so I'm going to

write it like that

and then I'm going to draw this as a

substituent so we have an O ch3 group so

notice that one carbon one we have this

group which is called a methoxy group as

a substituent so it's one methoxy I

think or simply methoxy I think the

ethane is the parent chain of the two

carbons on the left so this is the IU

pack name for this particular ether

let's try another example

let's name this particular ether feel

free to pause the video and work on this

example on the right we have two carbons

on the Left we have four carbons so we

have a butyl group on the left and an

ethyl group on the right so it's already

in alphabetical order so it's called

butyl ethyl ether now that's the common

name what about the IU pack name so

let's read wrong so here's the longest

chain it's four carbons and the

substituent is this portion of the

molecule

Oh ch3 is known as methoxy as a

substituent because it has only a methyl

group here we have an ethyl group

attached to it so this is called a foxy

so it's one of foxy and the parent name

is butane it's a four-carbon alkane so

one ethoxy butane that's the IU PAC name

for that example now how about this

example how can we name this particular

ether so notice that we have an ethyl

group on both sides so we have to group

ethyl groups it's not called ethyl ethyl

ether but it's simply diethyl ether so

that's the common name now for the IU

pag name we're going to treat one side

as a substituent so I'm going to write

it as och - ch3 so once again this is a

foxy and it's on carbon 1 but if it was

here this would be carbon 1 so for a two

carbon chain no matter where you put the

epoxy group it's going to be on carbon 1

so you could just call it foxy add thing

and that's all you got to do for this

one here's another one that we could try

what's the common name for this

particular ether now on the right we

have an fo group on the Left we have

three carbons but based on the way it's

connected this is an isopropyl group so

e comes before I so this is ethyl

isopropyl ether

now what about the are you packing what

is it for this particular molecule so

I'm going to redraw it first I'm going

to draw these three carbons because

that's the longest chain so two three

and on carbon 2 I'm going to draw the

efox II group so I'm going to rewrite it

like this so you can clearly see that

the attack C group is on carbon 2 so

it's 2 we foxy and for a 3 carbon alkane

it's propane so - we thought C propane

that's di you pack name for this ether

now what about this one let's focus only

on the IU pack name what is the IU

packing for the structure so first we

need to identify the longest shame

should we count it from right to left or

left to right if we count it from left

to right we're going to have two

substituents at three and four we have

an epoxy group at three and a methyl at

four if we count it from right to left

the methyl is going to be on carbon 2

instead of carbon 4 so you want to count

in the direction that's going to give

you the lower numbers so we want to

count that way so now we got to

alphabetize it which one comes first

o'clock C or methyl he comes before M so

we're going to put the epoxy group first

so it's 3 a foxy - 2 methyl and four

five carbon chain

it's pentane

so this is the answer now what about

this one let's say if we have not only

an ether but also an alcohol group and

also a halide how can we name this

particular compound so which group has

more priority the alcohol or the ether

alcohols typically have more priority

than either's so to name it we're going

to give the OHS to lower number so we're

going to count it from right to left

now we have a bromo group on 4 and a

methoxy group on 3 so BR is going to be

written first because it has the lower

alphabet so it's 4 bromo - 3 - a methoxy

instead of ethoxy because the ether has

a methyl group and then - - we have a

five carbon change so instead of saying

pentane is going to be Penton all the o

h is on carbon - so that's it for bromo

3 methoxy - Penton all now what about

this example

Kalka we name this particular ether

let's start with the common name so on

the right we have a methyl group on the

Left we have a cyclo pencil group

because it has a ring with five carbons

and C comes before M so it's going to be

called cyclo pencil methyl ether now

what about the IU pack name well first

we need to identify the longest ring and

it's clearly the five carbon ring so

that's going to be called cyclopentane

and this is the substituent which is

known as methoxy so it's simply called

methoxy cyclo pentene well that is not

cyclopentane I forgot the Y here it is

try this one let's say if we have a six

carbon ring and an O ch2 ch3 group so

let's start with the common name on the

right we have an ethyl on the Left we

have a cyclohexyl group so C comes

before E in the alphabet so it's cyclo

hexa ethyl

ether

now for the eye you pack name the six

carbon ring is the long chain so that's

going to be called cyclo hexane and the

substituent is the foxing and it's

automatically on carbon one so we can

just write it as a foxy cyclohexane now

what if you have a molecule that looks

like this

how would you name it so we have two

ethers so I'm going to redraw

so what is di you pack name for this

compound so this is a substituent that's

methoxy we have another methoxy group

and one of them is on carbon one the

others on carbon 2 now the longest chain

is the 2 carbon chain in the middle

which is ethane and since we have two

methoxy group so we can call it dye

methoxy so it's one two - dimethyl see

that thing

now let's try one last example similar

to this one

how would you name this either so this

is a eath oxy group and here we have

another foxy group now we want to count

it from left to right not right to left

so we can get the lower numbers so we

want to make this 1 2 3 4 5 6 7 8 9 the

longest chain is 9 which is nonane we

have a foxy group at 1 & 6 so it's going

to be 1 comma 6

- dieth oxy nani and that's it so now

you know how to name ethers