CHM616 - Summer 2010 Dr. John Harwood (Chemistry) and Dr ...

CHM616 - Summer 2010 Dr. John Harwood (Chemistry) and Dr. Huaping Mo (MCMP) Overview This class is designed to give you experience with a variety of operations and experiments on a Bruker Avance-DRX NMR spectrometer. The experiments are chosen to help further your understanding of NMR and to expose you to techniques that can be useful in the support of your research. The class has one lecture and two laboratory meetings per week. Lectures are on Mondays, 10:00 a.m. to 11:50 a.m., in room 3102 BRWN. Some lecture time may be used to give demonstrations on the spectrometer. The class textbook is: High-Resolution NMR Techniques in Organic Chemistry, Timothy D.W. Claridge, Elsevier 2009, ISBN 978-0-08-054818-0 (paperback). Labs will be done in groups of two. Each group will have two lab meetings per week with each

meeting being up to three hours. Lab meeting times will be scheduled during the first meeting of

class and will be arranged keeping the students' schedules, the instructors' schedules and efficient

use of the spectrometer in mind. Unless noted otherwise the labs will meet in room 367 WTHR

at the Bruker DRX500-1 spectrometer. Labs will not meet on Mondays.

Grading for the class will be as follows:

30% attendance;

40% lab reports;

30% final exam.

The final exam will comprise a take-home exam part and a structure-determination part. Each

part is worth 50% of the final exam grade. For the structure-determination part, you will be

given an unknown sample and using NMR techniques and the sample's molecular formula you

will attempt to determine its structure. We will have four unknown samples for you to choose

from. You will be given the molecular formula of your sample after you have selected it. You

will be able to start acquiring spectra for the structure-determination part on Thursday, July 29th.

The take-home exam will be given out on Monday, August 2nd. Both parts must be turned in by

5:00 p.m. on Friday, August 6th. Since attendance is a significant portion of the final grade please do not miss or be late to lecture or lab. However, if you finish a lab early you are free to leave at that point. Lab reports are to be handed in as hard-copy. Each student will hand in their own lab reports. Lab reports are due one week after the completion of the current week's lab meetings. All relevant spectra should be included, along with any necessary results and answers to questions. Since this is a practical course every spectrum that you turn in must be of proper quality - points will be deducted for obviously poor shimming or phasing, for example. Make sure spectra are referenced correctly and that title texts are appropriate and informative. Do not delete any data on the spectrometer computer - you may need it later.

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Syllabus Week 1 - June 14th - 18th Claridge chapters 2 and 3 Lecture Introduction to the class and overview NMR basics - energy levels, pulses, rotating frame, etc. NMR observables - chemical shifts and coupling constants NMR spectrometer overview - lock, observe, decoupling Labs Introduction to the DRX500-1 spectrometer and TopSpin software Overview of standard 1H and 13C acquisition, processing, integration and plotting Resolution and window functions Macros and au-programs Spectrometer calibrations - probe tuning, shimming, pulses Signal-to-noise measurements for 1H and 13C Week 2 - June 21st - 25th Claridge chapters 2, 3 and 4 Lecture Pulse programs 1D 1H experiments with multiple irradiation Spin-locking Selective excitation Multipulse experiments - DEPT Relaxation Labs Pulse program files - text and graphics Relaxation experiments - 1H T1 measurement 1 H decoupling and nOe difference experiments Selective 1D 1H experiments - selective TOCSY and NOESY 13 C acquisitions with and without nOe 13 C DEPT experiments

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Week 3 - June 28th - July 2nd

Claridge chapters 4 and 6

Lecture/Demo Polarization transfer INEPT - various flavors Introduction to 2D - turning INEPT into HETCOR 2D NMR - HETCOR Labs Selective population transfer using a 1H - 13C coupled pair Non-selective population transfer - INEPT Variations on INEPT Introduction to 2D NMR using HETCOR 1 H - 13C heteronuclear correlations by short- and long-range couplings - HETCOR and COLOC Week 4 - July 5th - 9th


Lecture No lecture (July 4th holiday) - an overview will be given at the start of your first lab meeting Labs Homonuclear 2D 1H experiments - COSY, TOCSY, DQFCOSY, NOESY Phasing of 2D spectra Week 5 - July 12th - 16th


Lecture/Demo Field gradients in NMR Coherence-transfer pathways and gradient-filtering Homonuclear gradient-enhanced experiments Heteronuclear gradient-enhanced experiments - the "inverse" mode Gradient shimming Labs Gradient echoes and the 1D image Gradient shimming using 2H Homonuclear 2D 1H gradient-enhanced experiments - pfg-COSY, pfg-DQFCOSY 1 H and 13C heteronuclear 2D gradient-enhanced experiments - pfg-HMQC and HMBC

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Week 6 - July 19th - 23rd


Lecture/Demo Considerations for NMR of bio-molecules in H2O Water-suppression HSQC-type experiments Triple-resonance experiments Labs Shimming and gradient shimming on H2O samples Pulse calibrations with salty samples, pulse calibrations in the indirect mode HSQC experiments with 13C and 15N -labeled samples HSQC experiments with Y-nucleus decoupling Week 7 - July 26th - 30th Lecture Special topics - computer simulations of pulses, pulse sequences and spectra Special topics - quantitation by NMR Discussion of structure-determination project and selection of samples Labs First weekly lab meeting - offline simulations First weekly lab meeting - quantitation by NMR Second weekly lab meeting - start on structure-determination project spectra Week 8 - August 2nd - 6th Lecture Review Take-home final given out Labs Running necessary experiments - self guided NOTE: take-home exam and structure-determination projects are both due by 5:00 p.m. on Friday, August 6th.

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