Advanced structure elucidation by spectroscopy

General objective

This is a one week tutorial (guided problem solving). After a brief introduction of how to extract information from mass spectrometry (high resolution) and NMR spectroscopy (1D and 2D correlation spectra) the interpretation will be trained on exercises of variable complexity. The exercises are real spectra and will include some of the pitfalls, challenges and artifacts typical for real samples.

Learning objective

The participant will learn how to interpret NMR spectra from structurally well-defined samples (assignment) and how to deduce the unknown chemical topology from NMR spectra by solving problems with a mild guidance of the tutor. The practical work will typically be done in small groups (2 up to 4).

The learning speed will be individually adjusted by choosing the adequate complexity of the next task (exercise).

Exercises will be available as printouts and in electronic data (Bruker format) for using own software.

This course, however, will not offer guidance how to use software for processing NMR spectra or software for using NMR spectra for characterization or elucidation of structures. The participants should finally understand how such computer aided structure elucidation (by the combination of NMR correlation(s) and the information of chemical shifts) works and be able to judge its limitations.   

One of the structure elucidation(s) will be documented by the participants (written form) with a full description of how the structure hypothesis has been derived.


 

Contents

The course will introduce a set of 2D NMR experiments (homo- and hetero-nuclear) required for the spectroscopic characterization (of synthetic samples and isolates of unknown chemical structure, i.e.: topology)).

The focus is on the concept of information as obtained by

- high resolution mass spectra and the isotope cluster and

- by NMR-correlation experiments.

A formal description of structure elucidation (determining the chemical topology from observed spin-topologies) in terms of information theory will enable the participants to understand how structural elucidation (computer aided and done by humans) works and judge the quality and reliability of a structure determination. The format of a tutorial, i.e. solving problems with some guidance will train the own way of working on practical problems of structure verification and elucidation.

 

Participants

The course addresses PhD students and students working on their master thesis in

- synthetic organic chemistry

- natural product research

- forensic and pharmaceutical sciences

- other disciplines with interest in the confirmation and elucidation of the structure of organic compounds by NMR spectrospopy (with some help from mass spectrometry)

Requirements will be

- basic knowledge of NMR spectroscopy

- basic knowledge of chemical structures (organic chemistry)

Organizer: Professor Reinhard Wimmer, rw@bio.aau.dk  

Lecturers: Adjunct Associate Professor Herbert Kogler, AAU

ECTS:          4

Time:           28 August - 1 September 2023

Place:          Aalborg University

Deadline:    1 August 2023