NMR Spectroscopy Twodimensional NMR http www univlille 1

1 D NMR Pulse Sequence Spectrum (Et. OH)

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

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

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

C, H Correlation by Polarization Transfer (HETCOR) HETCOR

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

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

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

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

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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

1 D NMR Pulse Sequence Spectrum (Et. OH)

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. 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

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

H, H- COSY Experiment

COSY & TOCSY

TOCSY of strychnine

NOESY of strychnine

C, H Correlation by Polarization Transfer (HETCOR) HETCOR

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 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 split by H, H spin couplings.

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

COSY

DQF-COSY

HMQC

HMBC

HSQC