Need help urgent with proton nmr Watch

username1422179
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The proton nmr spectra in pic 1 is of the structure in pic 2, but the peak around 7ppm represents protons on the two benzenes but the protons on both benzenes are not in the same environment so how do they contribute to one peak
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username1973239
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(Original post by uchihaitachi0023)
The proton nmr spectra in pic 1 is of the structure in pic 2, but the peak around 7ppm represents protons on the two benzenes but the protons on both benzenes are not in the same environment so how do they contribute to one peak
I'm pretty sure there's more than one peak at around 7ppm
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banter phalanx
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I would say that it isn't one peak. from the spectrum it looks like 2 separate peaks very near to each other. u can see 1 is significantly taller. Idk if this is the official reason but thats how i see it.

you would probably cross-reference with the carbon NMR and realise there was another benzene (i believe there were 14 carbon environments)
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username1422179
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(Original post by banter phalanx)
I would say that it isn't one peak. from the spectrum it looks like 2 separate peaks very near to each other. u can see 1 is significantly taller. Idk if this is the official reason but thats how i see it.

you would probably cross-reference with the carbon NMR and realise there was another benzene (i believe there were 14 carbon environments)

Originally I didn’t think it was 1 peak but then the integration trace was 7, Normally if there’s 2 different peaks it would give the relative proton in each environment separately eg 4 in one and 3 in the other not the total in both environments
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username1422179
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(Original post by TomTomSatNavv)
I'm pretty sure there's more than one peak at around 7ppm
Okay let’s say the two benzenes both make 2 separate peaks and we know that 1 peak means 1 proton environment, from the molecule I’ve counted 2 proton environments on the second benzene ring and three proton environments on the first benzene ring , shouldn’t there be five peaks around the 7ppm range then or have I counted the environments wrong
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charco
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It's not one peak - it's a multiplet, typical of benzene rings.

Actually there are two sets of benzene ring signals superimposed.
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(Original post by charco)
It's not one peak - it's a multiplet, typical of benzene rings.

Actually there are two sets of benzene ring signals superimposed.
say if I had a spectrum that had a doublet a triplet and singlet that means there’s 3 proton environments but r u saying a multiplet for benzene doesn’t mean 1 proton enviroment?, because I thought one peak mean u get one proton environment and the other peaks apart of the multiplet r just due to splitting due to adjacent protons ?
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charco
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(Original post by uchihaitachi0023)
say if I had a spectrum that had a doublet a triplet and singlet that means there’s 3 proton environments but r u saying a multiplet for benzene doesn’t mean 1 proton enviroment?, because I thought one peak mean u get one proton environment and the other peaks apart of the multiplet r just due to splitting due to adjacent protons ?
Substituted benzene protons are all in slightly different environments, and adjacent protons in different environments split each other and appear at slightly different chemical shifts. The result is usually a messy signal appearing at about 7.0.

Monosubstituted benzene has 3 different environments.

1,4-disubstituted has 2 different environments,

1,3-disubstituted depends on whether the two substituents are the same or not. If they are there are 3 different environments, if they are different there are 4 different environnments.

You see, it gets tricky, but not impossible, to analyse at high resolution. In fact the pattern gives important clues as to positions of poly-substitution.
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