NMR Nuclear Magnetic Resonance .


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Proton with Carbon-13 coupling. Proton with Fluorine-19 coupling. Fluorine-19: Fluoroacetone. Phosphorus-31. Phosphorus-31: Coupling with 1H. Phosphorus-31 Coupling with 13C. Phosphorus-31. Phosphorus-31. . . . . . 28 Hz. . . . . . 8Hz. dt. Phosphorus-31. 9 Hz. 39 Hz. NMR
Transcripts
Slide 1

NMR N uclear M agnetic R esonance Heteronuclear NMR: Index NMR-rudiments H NMR-Symmetry Heteronuclear-NMR

Slide 2

Proton with Carbon-13 coupling

Slide 3

Proton with Fluorine-19 coupling

Slide 4

Fluorine-19: Fluoroacetone

Slide 5

Phosphorus-31

Slide 6

Phosphorus-31: Coupling with 1 H

Slide 7

Phosphorus-31 Coupling with 13 C

Slide 8

Phosphorus-31

Slide 9

AQ: P31 AQ: P31 Phosphorus-31 28 Hz 8Hz d t H1 decoupling

Slide 10

AQ: P31 39 Hz Phosphorus-31 9 Hz H1 decoupling NMR – From Spectra to Structures An Experimental approach Second release (2007) Springler-Verlag Terence N. Mitchellm Burkhard Costisella

Slide 11

Silicon, Mercury, Carbon

Slide 12

N15 NMR 10 mm tube 25% in CDCl3 Inverse gated D1=15 s Total time 12 hrs NMR – From Spectra to Structures An Experimental approach Second version (2007) Springler-Verlag Terence N. Mitchellm Burkhard Costisella

Slide 13

C-13 NMR

Slide 14

C-13 NMR: Quantitative?? In C-13, a few carbons can have long unwinding time : If the unwinding postponement is not sufficiently long, the long unwinding carbons won\'t accomplish full adequacy NOEs fluctuates for the different carbons Number of information focuses used to record the information won\'t not be adequate The productivity of the beat change depending if a flag is in the focal point of the window or as an afterthought.

Slide 15

NMR – From Spectra to Structures An Experimental approach Second version (2007) Springler-Verlag Terence N. Mitchellm Burkhard Costisella AQ: C13 Normal C13 measure time 1.5 hrs NOE exhibit, no coordination conceivable 2 C2 3 1 H1 decoupling 3 J CP = 2.3 3 J CP = 5.5 2 J CP = 7.2 1 J CP = 201.3 C3 P C HO 2 C1 1 J CP O C H 2 C H3

Slide 16

NMR – From Spectra to Structures An Experimental approach Second release (2007) Springler-Verlag Terence N. Mitchellm Burkhard Costisella AQ: C13 AQ: C13-NMR 2 d 1 3 C13, H-coupled H1 decoupling dd t q C2 P C HO 2 C3 1 J CP C1 O C H 2 C H3

Slide 17

NMR – From Spectra to Structures An Experimental approach Second version (2007) Springler-Verlag Terence N. Mitchellm Burkhard Costisella C13 coupling to proton 2 1 3 J C3-H2 = 7.9 2 J C3-H2\' = 5.4 C3 - Cl

Slide 18

AQ: C13 AQ: C13 AQ: C13 removing J values Me 3 J PC = 5.5 Hz H1 decoupling CH 2 specific dec. Quartet : CH 3 split by P (doublet) Split by CH2 triplet 1 J CH = 127.7 Hz

Slide 19

NMR – From Spectra to Structures An Experimental approach Second version (2007) Springler-Verlag Terence N. Mitchellm Burkhard Costisella AQ: C13 converse gated: joining Measuring time: 28 hours D1=120 s H1 decoupling D1 off

Slide 20

Multiplicity location DEPT : CH, CH3 CH 2 APT : CH, CH3 C , CH 2 Normal C13

Slide 23

NOE and decoupler

Slide 25

Carbon-13 Shift

Slide 26

Carbon-13 Shift Acid Amide Ester Ketone Aldehyde O C = O C – O C – O = C = C  C – C C=C 200 150 100 50 0

Slide 27

Alkanes d = - 2.5 + S nA 1 2 3 4 5 CH 3 - CH 2 - CH-CH 2 - CH3 6 CH3 d C 1 = - 2.5 + 1 a + 1b + 2g + 1d d C 1 = - 2.5 + 9.1 + 9.4 + 2(- 2.5) + .3 = 11.3 d C 2 = - 2.5 + 2 a + 2b + 1g + 2 o (3 o ) (Secondary carbon bound to tertiary) d C 2 = - 2.5 + 18.2 + 18.8 + (- 2.5) + (- 2.5) = 29.5 d C 3 = - 2.5 + 3 a + 2b + 2{3 o (2 o )} d C 3 = - 2.5 + 27.3 + 18.8 + (- 7.4) = 36.2 d C 6 = - 2.5 + 1 a + 2b + 2g + 1 o (3 o ) = 19.3

Slide 28

Alkanes d C 1 = - 2.5 + 1 a + 1b + 2g + 1d = 11.3 d C 2 = - 2.5 + 2 a + 2b + 1g + 2 o (3 o ) = 29.5 d C 3 = - 2.5 + 3 a + 2b + 2{3 o (2 o )} = 36.2 d C 6 = - 2.5 + 1 a + 2b + 2g + 1 o (3 o ) = 19.3 C2 C1 C3 C6 2 3 1 6

Slide 29

Substituted Alkanes CH 3 - CH 2 - CH 2 - CH 2 - CH 3 13.9 – 22.8 – 34.7 g b a CH 3 - CH 2 - CH - CH 2 - CH 3 OH CH = 34.7 + 41 = 75.7 ppm CH 2 = 22.8 + 8 = 30.0 ppm CH 3 = 13.9 + (- 5) = 8.9 ppm

Slide 30

CH = 34.7 + 41 = 75.7 ppm g b a CH 3 - CH 2 - CH - CH 2 - CH 3 CH 2 = 22.8 + 8 = 30.0 ppm OH CH 3 = 13.9 + (- 5) = 8.9 ppm

Slide 31

Shift Calculation: Select a reasonable model Use legitimate substituent impacts to anticipate the movements of the different carbons This gives an unrefined gauge without considering the geometry For cyclohexanes, substituents impacts are assembled as far as hub/tropical introduction

Slide 32

Cycloalkanes: Cyclohexane

Slide 33

Alkenes: Additivity rules

Slide 34

d-d+ CH 2 CH OMe CH 2 CH OMe 84.2 153.2 CH 2 CH 2 C d-d+ OEt CH C CH OEt C Unsaturated mixes: Electronic Effects Alkenes d-129.3 d+ 157 Allenes 75-97 200-215 Alkynes 65-90 ppm 23.2 89.4

Slide 35

Benzene Calculation

Slide 36

Nitro-4-Aniline

Slide 37

Example: Benzene Calculation => recognize isomers

Slide 38

H-NMR: isomers

Slide 39

Example: Benzene Calculation => recognize isomers Experimental movements 152.5, 136.6, 131.7, 126.3, 121.9, 116.3 Subst. C1 ortho meta para Me 9.2 0.7 -0.1 -3.0 CH(Me) 2 20.2 -2.2 -0.3 -2.8 OH 26.9 -12.8 1.4 -7.4 C1 = 128 + 9.2 – 2.8 +1.4 = 135.8 C2 = 128 + .7 - 0.3 –7.4 = 121.0 C3 = 128 – 0.1 – 2.2 + 1.4 = 127.1 C4 = 128 – 3.0 + 20.2 – 12.8 = 132.4 C5 = 128 – 0.1 – 2.2 + 26.9 = 152.6 C6 = 128 + 0.7 – 0.3 – 12.8 = 115.6 C1 = 128 + 9.2 – 2.8 – 12.8 = 121.6 C2 = 128 + .7 - 0.3 + 1.4 = 129.8 C3 = 128 – 0.1 – 2.2 - 7.4 = 118.3 C4 = 128 – 3.0 + 20.2 + 1.4 = 146.6 C5 = 128 – 0.1 – 2.2 - 12.8 = 112.9 C6 = 128 + 0.7 – 0.3 + 26.9 = 155.3

Slide 40

C1 = 128 + 9.2 – 2.8 +1.4 = 135.8 C2 = 128 + .7 - 0.3 –7.4 = 121.0 C3 = 128 – 0.1 – 2.2 + 1.4 = 127.1 C4 = 128 – 3.0 + 20.2 – 12.8 = 132.4 C5 = 128 – 0.1 – 2.2 + 26.9 = 152.6 C6 = 128 + 0.7 – 0.3 – 12.8 = 115.6 C2 C6 C3 C5 C1 C4

Slide 41

C1 = 128 + 9.2 – 2.8 – 12.8 = 121.6 C2 = 128 + .7 - 0.3 + 1.4 = 129.8 C3 = 128 – 0.1 – 2.2 - 7.4 = 118.3 C4 = 128 – 3.0 + 20.2 + 1.4 = 146.6 C5 = 128 – 0.1 – 2.2 - 12.8 = 112.9 C6 = 128 + 0.7 – 0.3 + 26.9 = 155.3 C3 C2 C5 C6 C4 C1

Slide 42

Carbonyls C=O Acid Ester

Slide 43

Carbonyls C=O Esters, Acid chlorides, Anhydrides, Amides, Carbamates

Slide 44

Carbonyls C=O : Ketones, Aldehydes

Slide 45

Coupling between 1 H and 13 C 1 J CH One security coupling is relative to % s character sp3 : ~125 Hz sp2: ~ 165 Hz sp : ~ 250 Hz Electronegative subst. Increment J CH-OR => J ~ 140 Hz CH-Cl => J ~ 150 Hz

Slide 46

Coupling between 1 H and 13 C sp 3 : 1 J CH Increase of coupling qualities with the electronegativity of the substituant : CH Z : Li 1 J CH = 98 Hz Z : C 1 J CH = 125-129 Hz Z : NR 1 J CH = 131-134 Hz Z : S 1 J CH = 138 Hz Z : OR 1 J CH = 140 Hz Z : Cl 1 J CH = 150 Hz Z : (OR) 2 1 J CH = 162 Hz Z : Cl 2 1 J CH = 178 Hz 1 J CH = 161 Hz 1 J CH = 180 Hz 1 J CH = 134 Hz 1 J CH = 137 Hz 1 J CH = 150 Hz

Slide 47

Coupling between 1 H and 13 C sp 2 : 1 J CH Increase of coupling qualities with the electronegativity of the substituant : =CH Z =C-H 1 J CH = 157 Hz 1 J CH = 238 Hz 1 J CH = 172 Hz 1 J CH = 250 Hz 1 J CH = ~200 Hz 1 J CH = 182 Hz 1 J CH = 202 Hz

Slide 48

Use of 1 J CH Extremely valuable for atoms where 1 J CH bigger than regular Diagnostic for alkynes (250 Hz) , epoxides (180 Hz) , hemiacetal (162 Hz) and cyclopropane (161 Hz)

Slide 49

Coupling between 13 C and 13 C : 1 J CC Measurable just on advanced compound Useful for setting up heartbeat groupings like INADEQUATE sp 3 R-C H 2 - C H 3 1 J CC = 35 Hz 1 J CC = 48 Hz sp 2 1 J CC = 44 Hz 1 J CC = 56 Hz 1 J CC = 54 Hz 1 J CC = 74 Hz 1 J CC = 74 Hz 1 J CC = 123 Hz

Slide 50

Coupling between 1 H and 13 C 2 J CH Usually little and hard to foresee Typical qualities: - 8 to +4 Hz

Slide 51

Coupling between 1 H and 13 C 3 J CH Depend on dihedral point between coupled cores: Karplus bend 0 edge : 3 J C-H ~ 3-7 Hz 90 edge : 3 J C-H ~ 0 Hz 180 edge: 3 J C-H ~ 7-12 Hz This conduct ( J cis < J trans ) is helpful uncommonly in sp2 carbons to help recognizing isomers

Slide 52

3 J : case of use Decouple OMe CO CN (J=13.7 Hz)

Slide 53

C-13 Coupling with other cores than H 1 J CD = 20 Hz 1 J CF = - 160 Hz 1 J CN = 6-8 Hz 1 J P-H = >600 Hz

Slide 54

15 N – NMR Amine

Slide 55

15 N – NMR Amide

Slide 56

15 N – NMR Aromatic

Slide 57

29 Si – NMR

Slide 58

29 Si 29 Si : H– NMR 3 J SiH - C H2 = 3.1 Hz Si-H: Septet

Slide 59

29 Si 29 Si : H– NMR d 1 J Si - H quintet 2 J CH2 - Si d 3 J H Si - Si-H : Quintet CH2 A B

Slide 60

19 F – NMR Index NMR-essentials H NMR-Symmetry Heteronuclear-NMR Dynamic-NMR

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