PHYSICAL METHODS IN ORGANIC CHEMISTRY
Students participating in the course will:
- know the main spectroscopic techniques used by chemists for the structural characterization of organic compounds (knowledge and understanding);
- know the instruments and their operating principle for the acquisition of the different types of spectra (knowledge and understanding);
- know the physical principles of UV, IR, RAMAN, NIR, and NMR (knowledge and understanding);
- understand and be able to analyze in-depth UV, IR, MS and NMR spectra of organic molecules;
- be able to get the structures of unknown compounds starting from the analysis of 1H- and 13C NMR, and 2D NMR spectra (applying knowledge and understanding);
- be able to explain in a clear way the analytical and logical process followed to obtain the structure of an unknown compound (communication skills).
It is necessary to have knowledge of organic chemistry. To access the final examination the student must have passed the Organic Chemistry I exam.
The course sets out to illustrate the main spectrometric and spectroscopic techniques used nowadays in the organic chemistry field for characterization and/or structural determination of organic compounds.
The analysis techniques that will be treated during the course are the following ones: elemental analysis, UV-Vis and chiroptical spectroscopy, near- and mid-infrared spectroscopy, Raman spectroscopy, mass spectrometry, mono- and bidimensional Nuclear Magnetic Resonance spectroscopy (1H- and 13C-NMR, and 2D NMR).
Besides the physical principles and the energy transitions involved in every technique, particular attention will be devoted to the analysis of spectra and how to obtain from them information for structural determination of an unknown compound.
Textbooks (one of the following to be chosen):
1. R. M. SILVERSTEIN, F. WEBSTER, "Identificazione Spettroscopica di Composti Organici", Casa Editrice Ambrosiana, Milano.
2. M. HESSE, H. MEIER, B. ZEEH, “Metodi spettroscopici in Chimica Organica”, EdiSES, Napoli.
This text is useful for the study of NMR technique:
A. RANDAZZO, "Guida Pratica all'interpretazione di Spettri NMR", Loghìa
1.D. L. Pavia, G. M. Lampman, G. S. Kriz, J. R. Vyvyan, Introduction to Spectroscopy, Books/Cole Ed.
2. J. KEELER, Understanding NMR Spectroscopy, John Wiley & Sons Inc, 2010.
3. T. CLARIDGE, High Resolution NMR Techniques in Organic Chemistry, Elsevier, 2008.
4. E. BREITMAIER, Structure Elucidation by NMR in Organic Chemistry - A Practical Guide, Wiley, 2002.
5. J. H. SIMPSON, Organic Structure Determination Using 2-D NMR Spectroscopy - a Problem-based Approach, Academic Pr, 2008.
6. R. EKMAN, J. SILBERRING, A. WESTMAN-BRINKMAL, A. KRAJ, Mass Spectrometry: Instrumentation, Interpretation, and Applications, Wiley, 2008.
Additional teaching material for students:
Pdf files of the lesson slides; examples of exercises given in previous examination sessions.
Frontal lessons will be used, in order that the students could acquire the knowledge and understanding of the spectroscopic techniques and the skills at the analysis of spectra. Exercises at different difficulty levels will be proposed, consisting in the analysis of spectra of compounds with known or unknown structure. The exercises will be carried out with the maximum involvement of the students with the aim to favor the acquisition of analytical skills, according to the above-mentioned objectives of the course.
The slides used by the teacher during the course will be published on Elly at the beginning of the course.
In the case of new restrictions limiting the access to university buildings, set by the Italian Government because of the COVID-19 health emergency, the course will be taught with frontal lessons via mixed in-presence and at-distance modality, or completely at-distance modality. In particular, the teacher will take lessons in the classroom with the help of a PC or a tablet, and the students will be able to attend the lessons in streaming modality by Teams platform. Moreover, each lesson will be registered and uploaded on Stream (Office365).
Verification of the achievements of the course will be carried out by a written examination followed by an oral one (in case the written exam has been passed).
The written examination takes 3.5 h and consists in two exercises: in the first one the student is required to elucidate the structure of an unknown compound of medium difficulty by analyzing 1H-NMR, 13C-NMR 1H-1H COSY spectra; in the second one it is required to elucidate the structure of an unknown compound of low difficulty by a combined analysis of NMR, IR, MS and UV spectra. During the exam, the student must have his own calculator and the tables of chemical shifts, IR absorptions, and mass fragments.
The written examination aims at verifying whether the student has developed the skill in applying the knowledge and understanding in the analysis of spectroscopic data, in fact he has to explain the logical process he has followed for solving exercises. The written examination will be judged sufficient whether the student will show good skills in analyzing spectra and in following correct logical processes in building the structure of the unknown molecule, even if he could not reach the correct structure.
Few days before the examination the teacher will give the students detailed instructions on the modality to access the examination.
The grades are given in thirtieths. A minimum of eighteen thirtieths is required as a threshold. The final mark is the average of the written and oral examination results.
In the case of a new COVID-related sanitary emergence, the written and oral examinations will proceed by remote, on the Teams platform.