anoymous1111
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Can you think of an isomer of c6h12 that would have 6 peaks on an NMR spectrum....i.e it has 6 different carbon environments.
Been trying for ages and haven't come up with one.
Thank you!


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charco
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(Original post by anoymous1111)
Can you think of an isomer of c6h12 that would have 6 peaks on an NMR spectrum....i.e it has 6 different carbon environments.
Been trying for ages and haven't come up with one.
Thank you!


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1-methyl-2-ethylcyclopropane
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anoymous1111
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(Original post by charco)
1-methyl-2-ethylcyclopropane
I can only see 4 carbon environments with that


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charco
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(Original post by anoymous1111)
I can only see 4 carbon environments with that


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There are 6.

Two carbons have to be identical in all ways in terms of everything to which they are attached to or else the environments are different.

I've drawn it out for you:

Name:  ethylmethylcyclopropane.jpg
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anoymous1111
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(Original post by charco)
There are 6.

Two carbons have to be identical in all ways in terms of everything to which they are attached to or else the environments are different.

I've drawn it out for you:

Name:  ethylmethylcyclopropane.jpg
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What is the difference between the environments of carbon 1 and 6, and the environments of carbons 2 and 4? Name:  ImageUploadedByStudent Room1442057214.908707.jpg
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charco
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(Original post by anoymous1111)
What is the difference between the environments of carbon 1 and 6, and the environments of carbons 2 and 4? Name:  ImageUploadedByStudent Room1442057214.908707.jpg
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Carbon 2 is directly attached to a methyl group, while carbon 4 is directly attached to an ethyl group.

Carbon 1 is directly attached to a cyclopropane unit, while carbon 6 is directly attached to a CH2 group.

These are different environments.
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FlowerFaerie087
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Hm. On that cyclopropane ring, the hydrogens pointing up are in different environments to the ones pointing down. If you have a model kit, build a model. Otherwise, imagine a flat triangle with different things pointing up and down on each corner. The 'up' H on the CH2 is closer to different things than the 'down' H.

I don't know whether this is beyond what you've learned so far, but it's my opinion that "white" lies shouldn't be told in science education, as they just lead students to be confused later on.
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Pigster
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The OP implies that it is C-NMR not H-NMR.
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FlowerFaerie087
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OH, got you! Was thinking, if you don't think about topicity it'd look like it had six H environments.

Worth noting this isn't the only possible answer
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