79092 - Spectrometric Identification of Organic Compounds with Laboratory

Learning outcomes

In this course the student will learn “hands-on” how to apply the most up-to-date spectroscopic methodologies such as multinuclear, 1D and 2D NMR, MS to the structural identification of complex organic molecules of natural origin as well as coming from multistep syntheses. The student will also learn how to deal with stereochemical assignments and how to observe reaction intermediates generated in catalytic processes. During the laboratory part the student will learn how to perform advanced organic transformations, and how to isolate and identify the products obtained.

Course contents

Theoretical part

Conformational analysis by NMR

1. NOE NMR
2. Variable temperature NMR
3. Relative configuration of stereogenic centers by NOE

Optical methods

1. Electronic circular dichroism – basics of theory and instrumentation
2. Exciton coupling and absolute configuration
3. Vibrational circular dichroism

Conformational analysis by QM methods

1. Overview of QM methods for conformational analysis
2. DFT fundamentals
3. Conformational analysis by DFT methods.
4. Ground state search and evaluation of relative energies.
5. Transition state for conformational analysis, atropisomers barrier evaluation
6. Calculations of observables: NMR chemical shifts and coupling constants
7. Calculations of excited states: TD-DFT simulations for absolute configuration
8. Optical activity calculation
9. Vibrational and electronic circular dichroism spectra calculations

Case studies by synergic combination of the above techniques for relative and absolute configuration of natural and synthetic organic molecules.

Laboratory:

1. NOE and variable temperature NMR
2. Acquisition of ECD spectra
3. Setup of calculations for AC determination.

Readings/Bibliography

S.M. Bachrach, Computational organic chemistry, Wiley, ISBN 978-1-118-29192-4

T.D.W. Claridge, High-Resolution NMR Techniques in Organic Chemistry 3rd Edition, Pergamon press, ISBN 978-0-080-99986-9

Comprehensive Chiroptical Spectroscopy: Instrumentation, Methodologies, and Theoretical Simulations, Volume 1, Wiley, ISBN 978-1-118-01293-2

N. Berova, P.L. Polavarapu, K. Nakanishi, R.W. Woody, Comprehensive Chiroptical Spectroscopy: Applications in Stereochemical Analysis of Synthetic Compounds, Natural Products, and Biomolecules, Volume 2 978-1-118-01292-5

Teaching methods

Powerpoint slides and laboratory sessions.

Assessment methods

Oral examination at the end of the course, discussing a manuscript previously provided by the teacher.

Teaching tools

All slides will be made available before the lessons.

Office hours

See the website of Andrea Mazzanti