chemists: please help!

skyebrewing · Oct 6, 2011

Taking an organic chemistry class and the professor gave us an assignment to draw 6 isomer possibilities of C5 H10 O. Then he notes to only use ring formations.
I have searched online but and found isomer possibilities but not rings.
Any help?

blizzard · Oct 6, 2011

Consider that the O could be part of the ring structure, or not.

skyebrewing · Oct 6, 2011

I thought about part of ring, then that becomes the beginning of ring, correct? Does just adding a branch on carbon 2( or 3 or 4) and so on change the iso or is it still the same?

blizzard · Oct 6, 2011

Now you're on to something. On a plain carbon ring (benzene for example), the location of a single functional group won't change the isomer. To prove this to yourself, draw a ring with one functional group and then rotate your drawing to see that it could be located on any of the carbons. However, with two functional groups you can get some isomers by arranging how the functional groups are related to each other (think ortho, para, meta). The same is true if the O is part of the ring... there are a couple of places a functional group can be added to that would create different isomers.

skyebrewing · Oct 6, 2011

Thanks!

DregAddict · Oct 7, 2011

You can only have one degree of unsaturation, so since you'll be using a ring in each isomer, then you can't use any double bonds. Think cyclic alcohols, and cyclic ethers. Cyclopentanol for example. Then a four C ring attached to -CH2-OH
Then 4C ring-O-CH3.
And two more would be an alcohol and an ether with 3C ring.

DregAddict · Oct 7, 2011

A 4C ring with an OH on one C and a methyl(CH3) group on a different C. If the constituents are on adjacent corners then it's one isomer. Move the constituents to opposite corners and it's another isomer.

skyebrewing · Oct 7, 2011

Thanks. I came up with a couple of those just by playing around with the rings that would leave enough bonds for all the H atoms. Made six rings and turned in my hw. Now lets see what the professor says..

DregAddict · Oct 7, 2011

Nice. Feel free to shoot any O-chem questions my way in a PM. I got As in Ochem I and II as well as Biochem, and it was only a few semesters ago so most of it's still fresh.