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NMR H Splitting

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myair

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what is the splitting pattern on one of the hydrogen in the benzene ring?

is it doublet ? or triplet ?
n+1
 

klutzy1987

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what is the splitting pattern on one of the hydrogen in the benzene ring?

is it doublet ? or triplet ?
n+1

It depends, if the ring is not substituted then there is no splitting because all the hydrogens are the same. Mono-subtiuted,di,tri-it depends I need a specific example.
 

joedat41

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if there is no substitution so even though the hydrogens on the benzene ring are neighbors, there is still no splitting because they are identical hydrogens. If the benzene ring is substituted then it is a different story.
 

klutzy1987

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if there is no substitution so even though the hydrogens on the benzene ring are neighbors, there is still no splitting because they are identical hydrogens. If the benzene ring is substituted then it is a different story.

What did I say wrong??
 

joedat41

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nothing just adding to was you said klutzy. i just adding that there is no splitting for identical neighbors. Its pretty much what you said just clarifying it
 

AfroChapin

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What if there are two equiavalent substituents on each side of the ring? I thought the aromatic hydrogens would then display two doublets?

The answer is a singlet, I don't understand why.
 

RCT PC CRN

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So is it fair to say that in order for splitting to occur you need different neighboring H?

So basically you will have minimum 2 signal if there is a splitting, right? Only one signal with splitting is not possible, like plain benzene.
 

gigawatt

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What if there are two equiavalent substituents on each side of the ring? I thought the aromatic hydrogens would then display two doublets?

The answer is a singlet, I don't understand why.

If you're talking about two identical substituents para to each other, as in p-xylene, then all four aromatic hydrogens are exactly the same, and do not split each other as explained above. In this case, all 6 methyl hydrogens are exactly the same as well, so the spectrum for p-xylene only shows two singlets.
 
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