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    asking to find compound

    got (ch3)3-c-ch2-N

    which is wrong somwhere

    thanks for helpp
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    You're very close with (CH3)3CH2N. You're right to think that an integration of 9 must be a (CH3)3 . You've just missed a few little things. First of all, you probably noticed that it doesn't add up to 87 so you need more atoms. You've identified on your IR that you've got an N-H stretch. Since it's a doublet, that indicates a primary amine i.e. NH2. So you should change that to (CH3)3CH2N2. You've now got a mass of 75. That's 12 mass units short. This happens to be the mass of a carbon atom. This slots in between the (CH3)3 and the rest of the molecule like this: (CH3)-C-CH2-NH2. Without that carbon, you had 6 bonds to your central carbon which is impossible.
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    (Original post by Kyri)
    You're very close with (CH3)3CH2N. You're right to think that an integration of 9 must be a (CH3)3 . You've just missed a few little things. First of all, you probably noticed that it doesn't add up to 87 so you need more atoms. You've identified on your IR that you've got an N-H stretch. Since it's a doublet, that indicates a primary amine i.e. NH2. So you should change that to (CH3)3CH2N2. You've now got a mass of 75. That's 12 mass units short. This happens to be the mass of a carbon atom. This slots in between the (CH3)3 and the rest of the molecule like this: (CH3)-C-CH2-NH2. Without that carbon, you had 6 bonds to your central carbon which is impossible.
    hi thanks for getting back in touch
    and dont seem to know where you have got the doublet from since all the peaks are singlet

    and i must have drawn my copy wrong i got (ch3)3-c-ch2-n
    which gives total of 85 so 2 short.........

    ....rite the peak between 2-3 is HC-N which trace of to 2 so does it mean its has 2 hydrogen on the carbon or the N think theres my shortage of two protons
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    When I said a doublet, I was referring to the IR spectrum. The N-H stretch appears in the 3000 - 3500 cm-1 region and you get one peak for secondary amines and two peaks (a doublet) for primary amides. You have two peaks so you have an NH2. This also happens to be where you have gone wrong. YOur nitrogen only has one bond to it. Nitrogen should have 3 bonds unless it's an ammonium ion. Add two more hydrogens to make it an NH2 and you get (CH3)-C-CH2-NH2 which has the correct mass.

    The peak between 2-3 ppm in the NMR is due to the NH2 protons. Two protons, so integrates to 2. It might have been useful if they told you what solvent this spectrum was run in. They might have told you that N-H protons are exchangeable and you won't see them but this is only true with D2O or deuterated methanol. In deuterated chloroform N-H protons are visible. In case you're wondering, this appears to be a low resolution spectrum so you can't see any splitting.
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    (Original post by Kyri)
    When I said a doublet, I was referring to the IR spectrum. The N-H stretch appears in the 3000 - 3500 cm-1 region and you get one peak for secondary amines and two peaks (a doublet) for primary amides. You have two peaks so you have an NH2. This also happens to be where you have gone wrong. YOur nitrogen only has one bond to it. Nitrogen should have 3 bonds unless it's an ammonium ion. Add two more hydrogens to make it an NH2 and you get (CH3)-C-CH2-NH2 which has the correct mass.
    hey thanks again
    done another last one just wanna make sure rite ( dont know what paper its is so cant find ms)



    ch3-ch2-c=0 - 0-ch2-ch2-ch3 (ester)

    thanks again
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    Almost. You've correctly identified the ester functionality and got the right mass but the connectivity is not quite right. The fact You have a 3H singlet at around 3.6 ppm means you must have a methyl group not adjacent to a proton containing carbon, but near an electronegative atom. That puts it on the oxygen side of the ester link. The 2H triplet at around 2.4 ppm is next to the next most electronegative thing, which is the CO. The triplet splitting is due to coupling to 2 protons. so it must be next to the carbonyl and and a CH2. You then have a 4H multiplet (mess) at 1.5 ppm with complex coupling so that's got to be -CH2-CH2-. It's a mess because the CH2 groups both have very similar chemical shifts so will overlap. They will also couple to each other as well as the protons either side of them, giving very complex splitting. The 3H triplet at 0.9 ppm must have 3 protons and not be near anything electronegative because the chemical shift is so low. This puts it at the end of the chain, coupling to the 2 adjacent CH2 protons, giving a triplet. So:

    CH3-CH2-CH2-CH2-CO-O-CH3
 
 
 
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