1 h nmr interpretation using the nmr mosaic. nmr spectra contain three pieces of information...
TRANSCRIPT
1H NMR Interpretation Using the NMR Mosaic
NMR Spectra contain THREE Pieces of Information
• Chemical Shift– Information about functionality
• Integration– Number of hydrogen MAKING the peak
• Multiplicity (splitting)– Number of NEIGHBOR hydrogens
ALL THREE must be used to solve spectrum
12 11 10 9 8 7 6 5 4 3 2 1
3 0 0 M H z ¹H N M RIn C D C l3
A L L R IG H T S R E S E R V E D© S igm a-A ld rich C o .
Chemical Shifts
OH, NH
Alkene
Adjacent to Oxygen
Adjacent to Cl, Br, I
Adjacent to double bond
Alkane-likeAromatic
Aldehyde hydrogen
Carboxylic acid hydrogen
Integration
• Rise of integral line indicates relative number of hydrogens
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3.5 3.0 2.5 2.0 1.5 1.0
300 MHz ¹H NMRIn CDCl3
ALL RIGHTS RESERVED© Sigma-Aldrich Co.
2
2
3
Multiplicity
• See one more peak than neighbor hydrogens– 0 hydrogens gives singlet
– 1 hydrogen gives doublet
– 2 hydrogens gives triplet
– 3 hydrogens gives quartet
Steps for Solving 1H NMR Spectra1. Calculate integration for each peak
a. #H = peak integration x (total # H’s / total integration)b. Smallest peak is often 1Hc. Peaks ~1 are often 3H (methyl)
2. Determine number of adjacent hydrogens from splitting- Number of peaks = n+1, where n = number of adjacent
hydrogens- Attach appropriate static cling(s)
3. Determine presence of functional group(s)- Attach functional group static cling(s)- Choose functional group Mosaic piece(s)
Calculate # H’s for each peak
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1.0
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300 MHz ¹H NMRIn CDCl3
ALL RIGHTS RESERVED© Sigma-Aldrich Co.
C3H7Cl
Calculate # H’s for each peak
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1.0
1.1
1.2
3.5 3.0 2.5 2.0 1.5 1.0
300 MHz ¹H NMRIn CDCl3
ALL RIGHTS RESERVED© Sigma-Aldrich Co.
C3H7Cl
2H 2H 3H
Make NMR Mosaic Pieces
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0.1
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1.0
1.1
1.2
3.5 3.0 2.5 2.0 1.5 1.0
300 MHz ¹H NMRIn CDCl3
ALL RIGHTS RESERVED© Sigma-Aldrich Co.
C3H7Cl
2H 2H 3H
-0.1
0.0
0.1
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0.6
0.7
0.8
0.9
1.0
1.1
1.2
3.5 3.0 2.5 2.0 1.5 1.0
300 MHz ¹H NMRIn CDCl3
ALL RIGHTS RESERVED© Sigma-Aldrich Co.
Make NMR Mosaic Pieces: C3H7Cl
H | ─C─ | H
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1.0
1.1
1.2
3.5 3.0 2.5 2.0 1.5 1.0
300 MHz ¹H NMRIn CDCl3
ALL RIGHTS RESERVED© Sigma-Aldrich Co.
H | ─C─ | H
CH2
Make NMR Mosaic Pieces: C3H7Cl
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0.0
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1.0
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1.2
3.5 3.0 2.5 2.0 1.5 1.0
300 MHz ¹H NMRIn CDCl3
ALL RIGHTS RESERVED© Sigma-Aldrich Co.
H | ─C─ | H
CH2 Fun
ct. G
rp.
Make NMR Mosaic Pieces: C3H7Cl
-0.1
0.0
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0.9
1.0
1.1
1.2
3.5 3.0 2.5 2.0 1.5 1.0
300 MHz ¹H NMRIn CDCl3
ALL RIGHTS RESERVED© Sigma-Aldrich Co.
X-
H | ─C─ | H
CH2 Fun
ct. G
rp.
Make NMR Mosaic Pieces: C3H7Cl
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0.1
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0.6
0.7
0.8
0.9
1.0
1.1
1.2
3.5 3.0 2.5 2.0 1.5 1.0
300 MHz ¹H NMRIn CDCl3
ALL RIGHTS RESERVED© Sigma-Aldrich Co.
X-
H | ─C─ | H
CH2 Fun
ct. G
rp.
Make NMR Mosaic Pieces: C3H7Cl
H | ─C─ | H
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0.7
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0.9
1.0
1.1
1.2
3.5 3.0 2.5 2.0 1.5 1.0
300 MHz ¹H NMRIn CDCl3
ALL RIGHTS RESERVED© Sigma-Aldrich Co.
X-
H | ─C─ | H
CH2 Fun
ct. G
rp.
Make NMR Mosaic Pieces: C3H7Cl
H | ─C─ | H
CH3
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0.7
0.8
0.9
1.0
1.1
1.2
3.5 3.0 2.5 2.0 1.5 1.0
300 MHz ¹H NMRIn CDCl3
ALL RIGHTS RESERVED© Sigma-Aldrich Co.
H | ─C─ | H
CH2 Fun
ct.
Grp
.
X-
H | ─C─ | H
CH2
CH3
Make NMR Mosaic Pieces: C3H7Cl
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0.1
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0.5
0.6
0.7
0.8
0.9
1.0
1.1
1.2
3.5 3.0 2.5 2.0 1.5 1.0
300 MHz ¹H NMRIn CDCl3
ALL RIGHTS RESERVED© Sigma-Aldrich Co.
H | ─C─ | H
CH2 Fun
ct.
Grp
.
X-
H | ─C─ | H
CH2
CH3
H |H─C─ | H
Make NMR Mosaic Pieces: C3H7Cl
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0.9
1.0
1.1
1.2
3.5 3.0 2.5 2.0 1.5 1.0
300 MHz ¹H NMRIn CDCl3
ALL RIGHTS RESERVED© Sigma-Aldrich Co.
H | ─C─ | H
CH2 Fun
ct.
Grp
.
X-
H | ─C─ | H
CH2
CH3
H |H─C─ | H
CH2
Make NMR Mosaic Pieces: C3H7Cl
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1.0
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1.2
3.5 3.0 2.5 2.0 1.5 1.0
300 MHz ¹H NMRIn CDCl3
ALL RIGHTS RESERVED© Sigma-Aldrich Co.
H | ─C─ | H
CH2 Fun
ct.
Grp
.
X-
H | ─C─ | H
CH2
CH3
H |H─C─ | H
CH2
1-chloropropane
Make NMR Mosaic Pieces: C3H7Cl
C6H12O2
0.00
0.25
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0.75
1.00
5.5 5.0 4.5 4.0 3.5 3.0 2.5 2.0 1.5 1.0 0.5 0.0
300 MHz ¹H NMRIn CDCl3
ALL RIGHTS RESERVED© Sigma-Aldrich Co.
C6H12O2
0.00
0.25
0.50
0.75
1.00
5.5 5.0 4.5 4.0 3.5 3.0 2.5 2.0 1.5 1.0 0.5 0.0
300 MHz ¹H NMRIn CDCl3
ALL RIGHTS RESERVED© Sigma-Aldrich Co.
H | ─C─ | H
Funct. G
rp.
CH
─ O ─
C6H12O2
0.00
0.25
0.50
0.75
1.00
5.5 5.0 4.5 4.0 3.5 3.0 2.5 2.0 1.5 1.0 0.5 0.0
300 MHz ¹H NMRIn CDCl3
ALL RIGHTS RESERVED© Sigma-Aldrich Co.
H |H─C─ | H
Fun
ct. G
rp.
H | ─C─ | H
Funct. G
rp.
CH
─ O ─
O || ─ C ─
C6H12O2
0.00
0.25
0.50
0.75
1.00
5.5 5.0 4.5 4.0 3.5 3.0 2.5 2.0 1.5 1.0 0.5 0.0
300 MHz ¹H NMRIn CDCl3
ALL RIGHTS RESERVED© Sigma-Aldrich Co.
H |H─C─ | H
Fun
ct. G
rp.
H | ─C─ | H
Funct. G
rp.
CH
H | ─C─ |
CH
3
CH2
CH3
─ O ─
O || ─ C ─
C6H12O2
0.00
0.25
0.50
0.75
1.00
5.5 5.0 4.5 4.0 3.5 3.0 2.5 2.0 1.5 1.0 0.5 0.0
300 MHz ¹H NMRIn CDCl3
ALL RIGHTS RESERVED© Sigma-Aldrich Co.
H |H─C─ | H
Fun
ct. G
rp. H
|H─C─ | H
CH
(2 of these)
H | ─C─ | H
Funct. G
rp.
CH
H | ─C─ |
CH
3
CH2
CH3
─ O ─
O || ─ C ─
C6H12O2: Isobutyl acetate
0.00
0.25
0.50
0.75
1.00
5.5 5.0 4.5 4.0 3.5 3.0 2.5 2.0 1.5 1.0 0.5 0.0
300 MHz ¹H NMRIn CDCl3
ALL RIGHTS RESERVED© Sigma-Aldrich Co.
─ O ─
O || ─ C ─
H |H─C─ | H
Fun
ct. G
rp.
H
|
H─
C─
|
H
CH
H | ─C─ | H
Funct. G
rp.
CH H | ─C─ |
CH
3
CH2
CH3
H |H─C─ | H
CH
C7H14O2
0.00
0.25
0.50
0.75
1.00
5.5 5.0 4.5 4.0 3.5 3.0 2.5 2.0 1.5 1.0 0.5
300 MHz ¹H NMRIn CDCl3
ALL RIGHTS RESERVED© Sigma-Aldrich Co.
C7H14O2
0.00
0.25
0.50
0.75
1.00
5.5 5.0 4.5 4.0 3.5 3.0 2.5 2.0 1.5 1.0 0.5
300 MHz ¹H NMRIn CDCl3
ALL RIGHTS RESERVED© Sigma-Aldrich Co.
─ O ─
H | ─C─ |
Fun
ct. G
rp.
CH
3CH3
C7H14O2
0.00
0.25
0.50
0.75
1.00
5.5 5.0 4.5 4.0 3.5 3.0 2.5 2.0 1.5 1.0 0.5
300 MHz ¹H NMRIn CDCl3
ALL RIGHTS RESERVED© Sigma-Aldrich Co.
─ O ─
H | ─C─ |
Fun
ct. G
rp.
CH
3CH3
H | ─C─ | H
CH2 Fun
ct. G
rp.
O || ─ C ─
C7H14O2
0.00
0.25
0.50
0.75
1.00
5.5 5.0 4.5 4.0 3.5 3.0 2.5 2.0 1.5 1.0 0.5
300 MHz ¹H NMRIn CDCl3
ALL RIGHTS RESERVED© Sigma-Aldrich Co.
─ O ─
H | ─C─ |
Fun
ct. G
rp.
CH
3CH3
H | ─C─ | H
CH2 Fun
ct. G
rp.
O || ─ C ─
H | ─C─ | H
CH2
CH3
C7H14O2
0.00
0.25
0.50
0.75
1.00
5.5 5.0 4.5 4.0 3.5 3.0 2.5 2.0 1.5 1.0 0.5
300 MHz ¹H NMRIn CDCl3
ALL RIGHTS RESERVED© Sigma-Aldrich Co.
─ O ─
H | ─C─ |
Fun
ct. G
rp.
CH
3CH3
H | ─C─ | H
CH2 Fun
ct. G
rp.
O || ─ C ─
H | ─C─ | H
CH2
CH3
H |H─C─ | H
CH
(2 of these)
C7H14O2
0.00
0.25
0.50
0.75
1.00
5.5 5.0 4.5 4.0 3.5 3.0 2.5 2.0 1.5 1.0 0.5
300 MHz ¹H NMRIn CDCl3
ALL RIGHTS RESERVED© Sigma-Aldrich Co.
─ O ─
H | ─C─ |
Fun
ct. G
rp.
CH
3CH3
H | ─C─ | H
CH2 Fun
ct. G
rp.
O || ─ C ─
H | ─C─ | H
CH2
CH3
H |H─C─ | H
CH
(2 of these)
H |H─C─ | H
CH2
C7H14O2: Isopropyl butyrate
0.00
0.25
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0.75
1.00
5.5 5.0 4.5 4.0 3.5 3.0 2.5 2.0 1.5 1.0 0.5
300 MHz ¹H NMRIn CDCl3
ALL RIGHTS RESERVED© Sigma-Aldrich Co.
H | ─C─ | H
CH2
CH3
H | ─C─ | H
CH2 Fun
ct. G
rp.
H |H─C─ | H
CH
H |H
─C
─ | H
CH
H |H─C─ | H
CH2
─ O ─
O || ─ C ─
H | ─C─ |
Funct. G
rp.C
H3 CH3
C6H12O2Cl
0.00
0.25
0.50
0.75
1.00
4.5 4.0 3.5 3.0 2.5 2.0 1.5 1.0 0.5
300 MHz ¹H NMRIn CDCl3
ALL RIGHTS RESERVED© Sigma-Aldrich Co.
C6H12O2Cl
0.00
0.25
0.50
0.75
1.00
4.5 4.0 3.5 3.0 2.5 2.0 1.5 1.0 0.5
300 MHz ¹H NMRIn CDCl3
ALL RIGHTS RESERVED© Sigma-Aldrich Co.
─ O ─
H | ─C─ | H
Funct. G
rp.
CH3
C6H12O2Cl
0.00
0.25
0.50
0.75
1.00
4.5 4.0 3.5 3.0 2.5 2.0 1.5 1.0 0.5
300 MHz ¹H NMRIn CDCl3
ALL RIGHTS RESERVED© Sigma-Aldrich Co.
─ O ─
H | ─C─ | H
Funct. G
rp.
CH3
H | ─C─ | H
CH2 Fun
ct. G
rp.
X-
C6H12O2Cl
0.00
0.25
0.50
0.75
1.00
4.5 4.0 3.5 3.0 2.5 2.0 1.5 1.0 0.5
300 MHz ¹H NMRIn CDCl3
ALL RIGHTS RESERVED© Sigma-Aldrich Co.
─ O ─
H | ─C─ | H
Funct. G
rp.
CH3
H | ─C─ | H
CH2 Fun
ct. G
rp.
X-
H | ─C─ | H
CH2 Fun
ct. G
rp.
C6H12O2Cl
0.00
0.25
0.50
0.75
1.00
4.5 4.0 3.5 3.0 2.5 2.0 1.5 1.0 0.5
300 MHz ¹H NMRIn CDCl3
ALL RIGHTS RESERVED© Sigma-Aldrich Co.
─ O ─
H | ─C─ | H
Funct. G
rp.
CH3
H | ─C─ | H
CH2 Fun
ct. G
rp.
X-
H | ─C─ | H
CH2 Fun
ct. G
rp.
H | ─C─ | H
CH2
CH2
C6H12O2Cl
0.00
0.25
0.50
0.75
1.00
4.5 4.0 3.5 3.0 2.5 2.0 1.5 1.0 0.5
300 MHz ¹H NMRIn CDCl3
ALL RIGHTS RESERVED© Sigma-Aldrich Co.
─ O ─
H | ─C─ | H
Funct. G
rp.
CH3
H | ─C─ | H
CH2 Fun
ct. G
rp.
X-
H | ─C─ | H
CH2 Fun
ct. G
rp.
H | ─C─ | H
CH2
CH2
H |H─C─ | H
CH2
C6H12O2Cl: Ethyl 4-chlorobutyrate
0.00
0.25
0.50
0.75
1.00
4.5 4.0 3.5 3.0 2.5 2.0 1.5 1.0 0.5
300 MHz ¹H NMRIn CDCl3
ALL RIGHTS RESERVED© Sigma-Aldrich Co.
─ O ─
O || ─ C ─ H
| ─C─ | H
Fun
ct. G
rp.
CH3
H |H─C─ | H
CH2
H | ─C─ | H
CH2 Fun
ct. G
rp.
X-
H | ─C─ | H
CH2
CH2
H | ─C─ | H
CH2Funct. G
rp.
NMR Mosaic Simplifies Interpretation of Complex Multiplets
• Adjoining pieces specify connectivity
• Interpretation is no longer “impossible”
Example: C4H9Cl
0.00
0.25
0.50
0.75
1.00
5.0 4.5 4.0 3.5 3.0 2.5 2.0 1.5 1.0 0.5
300 MHz ¹H NMRIn CDCl3
ALL RIGHTS RESERVED© Sigma-Aldrich Co.
Example: C4H9Cl
0.00
0.25
0.50
0.75
1.00
5.0 4.5 4.0 3.5 3.0 2.5 2.0 1.5 1.0 0.5
300 MHz ¹H NMRIn CDCl3
ALL RIGHTS RESERVED© Sigma-Aldrich Co.
X- H | ─C─ |
Fun
ct. G
rp.
CH
3CH2
Example: C4H9Cl
0.00
0.25
0.50
0.75
1.00
5.0 4.5 4.0 3.5 3.0 2.5 2.0 1.5 1.0 0.5
300 MHz ¹H NMRIn CDCl3
ALL RIGHTS RESERVED© Sigma-Aldrich Co.
X- H | ─C─ |
Fun
ct. G
rp.
CH
3CH2
H | ─C─ | H
Undetermined
Splitting
Example: C4H9Cl
0.00
0.25
0.50
0.75
1.00
5.0 4.5 4.0 3.5 3.0 2.5 2.0 1.5 1.0 0.5
300 MHz ¹H NMRIn CDCl3
ALL RIGHTS RESERVED© Sigma-Aldrich Co.
X- H | ─C─ |
Fun
ct. G
rp.
CH
3CH2
H | ─C─ | H
Undetermined
Splitting
H |H─C─ | H
CH
Example: C4H9Cl
0.00
0.25
0.50
0.75
1.00
5.0 4.5 4.0 3.5 3.0 2.5 2.0 1.5 1.0 0.5
300 MHz ¹H NMRIn CDCl3
ALL RIGHTS RESERVED© Sigma-Aldrich Co.
X- H | ─C─ |
Fun
ct. G
rp.
CH
3CH2
H | ─C─ | H
Undetermined
Splitting
H |H─C─ | H
CH
H |H─C─ | H
CH2
Example: C4H9Cl
0.00
0.25
0.50
0.75
1.00
5.0 4.5 4.0 3.5 3.0 2.5 2.0 1.5 1.0 0.5
300 MHz ¹H NMRIn CDCl3
ALL RIGHTS RESERVED© Sigma-Aldrich Co.
X-
H | ─C─ |
Fun
ct. G
rp.
CH
3CH2
H | ─C─ | H
Undetermined
Splitting
H
|
H─
C─
|
H
CH
H |H─C─ | H
CH2
Example: C4H9Cl
0.00
0.25
0.50
0.75
1.00
5.0 4.5 4.0 3.5 3.0 2.5 2.0 1.5 1.0 0.5
300 MHz ¹H NMRIn CDCl3
ALL RIGHTS RESERVED© Sigma-Aldrich Co.
X-
H | ─C─ |
Fun
ct. G
rp.
CH
3CH2
H
|
H─
C─
|
H
CH
H |H─C─ | H
CH2 H | ─C─ | H
CH
CH3
2-chlorobutane
NMR Mosaic Helps Students Catch Mistakes
• Mosaic pieces no longer match
• Focus students on incorrectly interpreted peaks
Example: C3H7Cl
-0.1
0.0
0.1
0.2
0.3
0.4
0.5
0.6
0.7
0.8
0.9
1.0
1.1
1.2
3.5 3.0 2.5 2.0 1.5 1.0
300 MHz ¹H NMRIn CD Cl3
A LL RIG H TS RESERV ED© S igm a-A ldrich Co.
H|
H─C─|H
CH2
H|
H─C─|H
H|
H─C─|H
CH2H|
─C─|H
CH3
CH3
H|
─C─|H
CH3
CH3
H|
─C─|H
CH2 Func
t. G
rp.H
|─C─
|H
CH2 Func
t. G
rp.H
|─C─
|H
CH2 Func
t. G
rp.H
|─C─
|H
CH2 Func
t. G
rp.
Incorrect piece as an example
C3H7Cl
X-
Example: C3H7Cl
-0.1
0.0
0.1
0.2
0.3
0.4
0.5
0.6
0.7
0.8
0.9
1.0
1.1
1.2
3.5 3.0 2.5 2.0 1.5 1.0
300 MHz ¹H NMRIn CDCl3
ALL RIGHTS RESERVED© Sigma-Aldrich Co.
H |H─C─ | H
CH2
H | ─C─ | H
CH3
CH3
H | ─C─ | H
CH2 Fun
ct.
Grp
.
X-Incorrect Match ↑
Example: C3H7Cl
-0.1
0.0
0.1
0.2
0.3
0.4
0.5
0.6
0.7
0.8
0.9
1.0
1.1
1.2
3.5 3.0 2.5 2.0 1.5 1.0
300 MHz ¹H NMRIn CDCl3
ALL RIGHTS RESERVED© Sigma-Aldrich Co.
H |H─C─ | H
CH2 H | ─C─ | H
CH2 Fun
ct.
Grp
.
X-Corrected Piece
Matches
H | ─C─ | H
CH2
CH3
Steps for Solving 1H NMR Spectra1. Calculate integration for each peak
2. For each peak:•Choose correct base Mosaic piece based on integration
- Determine number of adjacent hydrogens from splitting and add static cling tab(s) to base piece
- Determine presence of functional group(s) - Add functional group static cling(s) - Choose appropriate functional group Mosaic piece(s)
3. Put Mosaic pieces together, making sure all colors match and all functional group chemical shifts match.