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1 Draw a structure consistent with the following data:

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The MS shows a molecular ion at 59 amu. The IR spectrum shows a double-humped ... No peak shows up in the double bond region, C=C or C=O. So that leaves a ring. ... – PowerPoint PPT presentation

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Title: 1 Draw a structure consistent with the following data:


1
  •  1)  Draw a structure consistent with the
    following data
  • The MS shows a molecular ion at 59 amu.
  • The IR spectrum shows a double-humped strong
    absorbance at around 3300 cm1 (the only
    absorbance in the functional group region).

Odd molecular ion peak tells you there is a
nitrogen. 59-1445 45/123 carbons 45-369
hydrogens C3H9N. 2(3)2-910
The peak at 3300 cm1 tells us that the N is part
of an amine
2
2)   Either 2-butanone, 2-methyl-2-nitropropane,
3-pentanone, 1-nitropropane, nitroethane, or
2-bromopropane is responsible for the 1H NMR
spectrum shown. Draw the structure of the
responsible compound. (doublet and heptet)
3
There are two signals in the spectra so we can
eliminate 2-butanone, 2-methyl-2-nitropropane and
1-nitropropane because they have either more or
less than 2 types of protons.
Next you can eliminate 3-pentanone because it
would have a triplet and a quartet which is not
seen in the spectra.
Also nitroethane can be eliminated because it
would have a doublet and a quartet.
While the answer is 2-bromopropane which has a
doublet and a heptet.
4
3)  Either 2-butanone, 2-methyl-2-nitropropane,
3-pentanone, 1-nitropropane, nitroethane, or
2-bromopropane is responsible for the 1H NMR
spectrum shown. Draw the structure of the
responsible compound. (quartet, singlet and a
triplet)
5
Because there are 3 signals it is either
2-butanone or 1-nitropropane.
1-nitropropane should have a doublet, a quartet
and a triplet
While our answer, 2-butanone should have a
singlet, a quartet and a triplet..
6
4)  The molecular formula of a compound is
C6H12O. Determine the structure of the compound
based on its molecular formula and its 13C NMR
spectrum. (4 PEAKS)
7
First 2(6)2-122/21 so either a ring or double
bond.
No peak shows up in the double bond region, CC
or CO.
So that leaves a ring.
Four peaks and with this structure we have 4
different types of carbon.
8
5)  Identify the compound with molecular formula
C3H5Cl3 that gives the following 13C NMR
spectrum. (The resonance at 0 ppm is due to the
TMS standard, not the unknown.)
9
First, 2(3)2-5-30 so no double bonds or rings.
Secondly there are 3 peaks, so 3 different kinds
fo carbon.
So that leaves two choices that are correct.
10
6) What would the proton NMR peak look like for
the indicated hydrogen?
Because the two sets of adjacent protons are
equivalent this peak would follow the n1 rule
and be a septet.
11
7) What type of electromagnetic radiation is used
in nuclear magnetic resonance?
Radio waves
8) What is the most abundant peak in a mass
spectrum called?
Base peak
12
9)      Using the MS and IR spectra attached (1A
and 1B) propose the formula and structure of this
compound. (106 and 108)  
13
MS shows a molecular ion peak at 106 and a M2
peak at 108.. So 106-3571 so 71/125 carbons so
71-6011 hydrogens so C5H11Cl 2(5)2-11-10
However, there is a carbonyl peak in the IR
14
So need to add an oxygen. -CH4 gives C4H7ClO so
2(4)2-7-12/21 So this is taken by the CO
bond.
One more thing, there is no peak at 2750 so no
aldehyde, our carbonyl is a ketone
The first one can be eliminated because of the
base peak at 43 in the MS, a loss of 63 accounts
for the loss of a C2H4Cl group.
15
10)  What is the major product of the following
reaction?
16
11)  What is the major product of the following
reaction?
Br2
CCl4
17
12)  What is the major product of the following
reaction?
HBr
18
 8) What alkene should be used to synthesize the
following alkyl bromide?
19
9)  What alkene, when allowed to react with HBr,
would produce the following alkyl bromide? (There
is more than one correct answer.)
20
10)  What five-carbon alkene will give the same,
single product whether it reacts with HBr in the
presence or the absence of a peroxide?
21
11)  Draw the major product of the following
reaction, including its stereochemistry. (Use
squiggly bonds to indicate a reaction that is not
stereoselective.) Assume only one equivalent of
the reagent is available to react with the
substrate.
22
12)  Draw the major product of the following
reaction, including its stereochemistry. (Use
squiggly bonds to indicate a reaction that is not
stereoselective.) Assume only one equivalent of
the reagent is available to react with the
substrate.
23
13)
24
14)
25
15)
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