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Flashcards in Exam 3 Deck (15):
1

H-H COSY

-Correlation Spectroscopy
-important experimental factor but has no bearing on interpretation
-protons on carbons directly attached to each other

2

DQF- COSY

-Double Quantum Filtered H-H COSY
-remove or filter single quantum transitions so that only double-quantum or higher transitions remain
-reduce the number of methyl singlets by selecting only systems with at least two spins
-Deconvolutes the spectrum

3

H-C HETCOR

-Heteronuclear Correlation
-Carbon detected
-Low sensitivity
-Not common

4

H-C HMQC

-Heteronuclear Multiple Quantum Coherence
-Proton Detected
-More sensitive than HETCOR
-Eliminates long range coupling
-preserves directly attached coupling
-interprets protons directly attached to carbon

5

H-C HMBC

-Heteronuclear Multiple Bond Coherence
-Proton detected
-Can correlate quaternary carbons back to a proton signal
-Don't always see 2-3 bond correlations, sometimes see 4
-Interpret two to three bonds from carbon

6

C-C INADEQUATE

-Incredible Natural Abundance Double Quantum Transfer Experiment
-Similar to COSY but for Carbon
-Allows for sketching carbon skeleton unambiguously
-low sensitivity and long experimental times
-Interprets Carbon directly attached to one another

7

TOCSY

-Total Correlation Spectroscopy
-Allow us to see correlations among nuclei that are not directly coupled to each other but within same spin system
-Longer mixing times, all spins within spin system appear coupled
-Interpreted by following spin system proton signal to proton signal
-stringing together COSY correlations

8

HMQC-TOCSY

-2D Hybrid experiment
-Correlates one bond proton and carbon coupling but shows these correlations throughout an entire spin system
-used for complex carbohydrates and peptide systems

9

ROESY

-Rotating-frame Overhauser Effect Spectroscopy
-Useful for molecules of all sizes
-correlate protons that are close to each other in space
-useful for stereochemical assignment and 3D structure

10

NOESY

-Similar to ROESY
-useful only for large moelcules

11

Pulsed Field Gradient NMR

-Phase cycling takes times
-can greatly reduce the need for phase cycling thus shortening experiment time
-experiments can be run more efficiently and quickly

12

N NMR

-most useful of multinuclear scpectroscopy
-important for organic chemists, natural product chemists, pharmacology, and biochemistry
-order of magnitude less sensitive than carbon
-long t1 times (relaxes slowly)
-similar chemical shift to carbon
-protonation important to consider
-run decoupled to proton like carbon

13

F NMR

-ideal nucleus for NMR
-important for polymer chemistry, metabolism, biopharmaceuticals, magnetic resonance imaging, and fluorine labeled proteins
-interest involved for replacement of hydrogen in synthetic compounds
-couples like hydrgoen --> causes coupling in proton and carbon

14

Si NMR

-Used by organic and polymer chemists
- couples protons

15

P NMR

-Interest to organic and biochemists because of phosphorous containing functional groups and nucleic acids, ADP, and ATP
-chemical shifts do not vary much while oxidation states, attached groups, and others do
-couples protons and carbons
-important applications for metal-phosphine complexes and related compounds