NMR Spectroscopy Twodimensional NMR http www univlille 1

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NMR Spectroscopy Two-dimensional NMR http: //www. univ-lille 1. fr/lcom/RMN 2 D/resum 2 D_us/index_us. htm

NMR Spectroscopy Two-dimensional NMR http: //www. univ-lille 1. fr/lcom/RMN 2 D/resum 2 D_us/index_us. htm

1 D NMR Pulse Sequence Spectrum (Et. OH)

1 D NMR Pulse Sequence Spectrum (Et. OH)

Four periods in 2 D experiment Preparation spin system relaxes and then excited by

Four periods in 2 D experiment Preparation spin system relaxes and then excited by r. f. Evolution (t 1) chemical shifts & spin-spin couplings evolve. This is the timedomain which is incremented during a 2 D experiment Mixing r. f. pulses are applied and create observable transverse magnetization Detection (t 2) observable transverse magnetization is recorded. It is usually labeled with t 2

2 D NMR 1. Primary 2 D matrix consists a series of FIDs. 2.

2 D NMR 1. Primary 2 D matrix consists a series of FIDs. 2. A set of 1 D NMR spectra is obtained by Fourier transformation with respect to t 2 3. The signals of each transformation may differ in amplitude and phase. A second Fourier transformation with respect to t 1 yields the final 2 D matrix with frequency axes F 1 and F 2 1. 2. 3.

2 D NMR Pulse Sequence Spectrum

2 D NMR Pulse Sequence Spectrum

2 D NMR

2 D NMR

2 D NMR

2 D NMR

2 D NMR

2 D NMR

2 D J-resolved COSY 45. COSY 90. COSY DQF. TOCSY. COSY L. R. TOCSY

2 D J-resolved COSY 45. COSY 90. COSY DQF. TOCSY. COSY L. R. TOCSY Relayed COSY. (with one homonuclear relayed). NOESY. ROESY.

2 D J-resolved spectroscopy

2 D J-resolved spectroscopy

H, H- COSY Experiment

H, H- COSY Experiment

COSY & TOCSY

COSY & TOCSY

TOCSY of strychnine

TOCSY of strychnine

NOESY of strychnine

NOESY of strychnine

C, H Correlation by Polarization Transfer (HETCOR) HETCOR

C, H Correlation by Polarization Transfer (HETCOR) HETCOR

HMQC The HMQC experiment provides correlation between protons and their attached heteronuclei through the

HMQC The HMQC experiment provides correlation between protons and their attached heteronuclei through the heteronuclear scalar coupling. HMBC The HMBC experiment suppresses correlations via 1 JC, H while 2 J, 3 J can be conserved. HSQC The HSQC experiment is in fact a double INEPT experiment. This experiment correlates protons with their directly attached heteronuclei. (G. Bodenhausen and D. J. Ruben, Chem. Phys. Lett. , 69, 185 (1980)

Basic HMQC Experiment F 2 displays the doublets with the spin coupling constant 1

Basic HMQC Experiment F 2 displays the doublets with the spin coupling constant 1 J(C-H) in addition to the H, H spin coupling.

HMQC with Decoupling Only singlets are displayed in F 2. These signals are further

HMQC with Decoupling Only singlets are displayed in F 2. These signals are further split by H, H spin couplings.

Basic HMBC Experiment Cross signals caused by 1 J of C-6 and C-3 are

Basic HMBC Experiment Cross signals caused by 1 J of C-6 and C-3 are still observable but those arising from 3 J and 2 J are predominant.

Basic HSQC Experiment

Basic HSQC Experiment

COSY

COSY

DQF-COSY

DQF-COSY

HMQC

HMQC

HMBC

HMBC

HSQC

HSQC