ToothDoctor

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Hi...I'm new here! Could someone please help me out here?!?! I'm completely lost when it comes to figuring out how many peaks (and whether they are singlets, doublets, etc.) a certain molecule gives for 1H NMR. I'm equally lost when it comes to 13C NMR. I have read the Kaplan book over and over again and it seems greek to me. Does anyone have a clear simple explanation with a couple of examples? I appreciate it...Thanks.
 

ItsGavinC

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I don't have time for any explanations right now, but I can tell you that the odds of having any C NMR on the DAT are slim to none (I don't think I've ever heard of a question with C NMR!). There's a better chance of having H NMR, although I didn't have any of those either on my DAT.
 

vixen

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here's a quick ex:


if you have R----CH2-CH3

the h's on the ch3 are equivalent....therefore, they will all get the same splitting pattern...look 1 c away from them and how many H's do you see? 2 so 2=n and N+1=3 so its a 3H triplet. The CH2 has its n=3, so n+1=4 so its a 2H quartet.....

if you had

CH3-CH2-O-CH2-CH3

the two methyl groups are equivalent here (equivalent meaning they're in the same chemical environment....right next to a CH2 and then and O) so the methyls would get One big splitting pattern of: 6h triplet

the ch2's are also equal so they'd be a 4H quartet...

hope this helps :)
 
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