The general aim of the course is the aquisition of the necessary skills in advanced mono and bidimensional spectroscopic techniques for the determination of a molecular structure. D1. Knowledge and understanding: students at the end of the course will have a practical knowledge of the basic principles of NMR and the main mono- and twodimensional tecniques, and of the modern instrumentation. D2. Applying knowledge and understanding: by applying the aquired knowledges students at the end of the course will be able determine the structure of complex organic molecules at starting from sets of mono- and bidimensional spectra. D3. Making judgements: Students at the end of the course will be able to select in autonomy the NMR tecniques, among the ones studied, to resolve a structure determination problem. D4. Comunication skills: students are expected to present with appriopriate language the aquired concepts. D4 Abilità comunicative: Gli studenti dovranno essere in grado alla fine del corso di esporre con chiarezza e con linguaggio corretto i concetti acquisiti. D5. Learning abilities: Students are expected to learn from lessons, from the book, and to elaborate in autonomy the concepts given in the course aimed at the resolution of complex exercises.

Fundamentals of spectroscopy. Fundamentals of organic chemistry.

Nuclear magnetic resonance spectroscopy. General principles, modern instrumentation, fundamental parameters, advanced one- and two-dimensional techniques. Advanced exercises in the structural determination of organic molecules.

Basic One- and Two-Dimensional NMR Spectroscopy, by H. Friebolin, Wiley. Slides of the lectures are available in Moodle

Mono and bidimensional Nuclear Magnetic Resonance Techniques applied to proton and carbon. PROGRAM 1. NMR GENERALITY The nuclear spin. Angular and magnetic moment. Properties of NMR active nuclei. Giromagnetic ratio. Absolute frequence; Sensitivity and receptivity. Nuclei in a magnetic field. Directional quantization. Larmor precession. Energetic states and spin transitions. Larmor equation. Resonance condition. Population distribution. Vectorial representation of magnetization. Continuous wave methods. Pulse methods. The laboratory and the rotating frame. 90° and 180° pulses. Phase coherence. Pulse Calibration. Relaxation. Longitudinal and transversal relaxation. Bloch equations. T1 measurement with inversion recovery sequence. T2 and lineshape. T2 measurement with spin echo sequence. T1/T2 relationship. Fourier transform. S/N ratio. Chemical shift: definition and vectorial representation in the rotating frame. The shield constant. 2. INSTRUMENTATION The superconducting cryomagnet. The probe. the shim coils. Sample preparation. Spectrometer preparation. Lock. Tuning. Matching. Shimmming. Data aquisition. FID sampling, Nyquist theorem. ACD. Digital resolution. Zero filling. Linear prediction. Window functions, apodization. The ’ADC dynamic range. The receiver gain. 3. 1H. CHEMICAL SHIFT Electronic and steric effects. Diamagnetic local anisotropy. Correlation tables. 4. SPIN SPIN COUPLING Homo and heteronuclear coupling. Fermi theory. Chemical and magnetic equivalence. Pople notation. 5. ANALYSIS OF SPIN SYSTEMS Two (AX, AB), three (AMX; ABX; ABC), four (AX3, AB3; A2X2; A2B2; AA’XX’; AA’BB’; AB2C), five (A2X3; A2B3; ABX3) spin systems. First order multiplets. Coupling constants J: geminal, vicinal, long range. Karplus equation. 6. DOUBLE RESONANCE EXPERIMENTS NOE, principles and applications. Homonuclear decoupling 1H - 1H experiments. . 7. 13C NMR: the sensitivity problem. 13C- 1H broad band decoupling, inverse gated decoupling, gated broad decoupling, off resonance decoupling. 13C[H] direct and indirect couplings, coupling constants. 13C chemical shift: ibridation effects, electronic and steric effects. 8. COMPLEX SEQUENCES. J modulated spin echo. APT (Attached Proton Test). SPT (Selective Polarization Transfer) INEPT (Insensitive Nuclei Enhaced by Polarization Transfer) DEPT (Distorsionless Enhacement by Polarization Transfer) INADEQUATE (Incredible Abundance Double Quantum Transfer Experiment) TOCSY 1D (Total Correlation Spectroscopy). Gradient fields. 9. NMR 2D Generalities. Basic scheme of a 2D experiment: preparation, evolution, mixing time, aquisition. 2D shift homocorreleted tecniques: COSY, COSY-beta, DQF-COSY, TOCSY, INADEQUATE. 2D shift heterocorrelated: HETCOR, HMQC, HSQC, HMBC. Through space correlatied tecniques: NOESY-2D, ROESY. Diffusion Spectroscopy. Chemical exchange. J correlated tecniques. Notes on 3D tecniques.

Lectures for a total of 48 hours, about 8 of which are devoted to illustrating practical examples of characterization of molecules by a combination of one- and two-dimensional spectra.

The degree of knowledge attained is ascertained by an oral examination that includes an exercise in interpreting a series of one- and two-dimensional NMR spectra, and a number of open-ended questions exploring the theory in depth. Students must demonstrate theoretical knowledge of the topics covered and the ability to apply this knowledge in practical examples. The exam grade is in 30/30 with the pass threshold set at 18/30.