CHEMISTRY OF HETEROCYCLIC COMPOUNDS
- Overview
- Assessment methods
- Learning objectives
- Contents
- Bibliography
- Teaching methods
- Contacts/Info
A deep knowledge of the topics tackled during the previous courses of Organic Chemistry, in particular concerning properties of aromatic compounds.
The final examination consists in a two-step procedure with written and oral tests. The former is usually structured in ten exercises on different topics, including nomenclature, guided synthesis by knowledge of reagents, planning of synthesis of aromatic compounds, acidity and basicity scale of different compounds, structure identification and separation of mixture of organic compounds. During the oral test, students will be examined on all the topics tackled during the lessons. The final mark is the average, weighted on the basis of the credits, of the partial mark of parts A and B of the course.
The course aims at increasing students’ knowledge in the field of the heterocyclic chemistry, highlighting the importance of heterocycles in drugs and innovative materials.
At the end of the course, students will be able :
1) to knowledge properties and reactivity of heterocyclic compounds;
2) to identify the synthetic strategies for the heterocyclic systems, focusing on the reaction intermediates;
3) to plan a convenient access of heterocycles in total synthesis or in complex synthetic sequences.
1. Structure of heterocyclic systems (4 hours). Nomenclature of single three-to-seven-membered heterocyclic rings. Nomenclature of heteropolycyclic systems. Electronic distribution of furan, pyrrole, thiophene and their benzo-fused derivatives, pyridine and its benzo-fused derivatives; pyrylium salts; imidazole, oxazole, thiazole, pyrazole, isoxazole; diazines and their benzo-fused derivatives; polyazoles e polyazines. Basicity of nitrogen-containing heterocyclic systems.
2. Reactivity of heterocyclic systems (12 hours). Reactivity of heteroaromatic systems: behaviour vs electrophiles and nucleophiles, reduction and oxidation, behavior as alkenes, reactivity at the pseudo benzylic position. Hydroxy derivatives of heteroaromatic systems: keto-enol tautomerism, reactivity as nucleophiles. Amino derivatives of heteroaromatic systems: basicity, diazotization reaction. Nitrogen-containing heterocycles N-oxides: synthesis, electronic distribution, reactivity. Quaternary salts of aromatic nitrogen-containing heterocycles.
3. Synthetic strategies for heterocycles (24 hours). Intramolecular nucleophilic substitutions, intramolecular aromatic electrophilic substitutions, intramolecolar condensation, cyclocondensation. Transition metal-catalyzed reactions for functionalization and synthesis of heterocyclic compounds: Heck reactions, cross-coupling reactions, Wacker-type reactions, Buchwald-Hartwig reaction, Chan-Lam reaction. Domino reaction for the synthesis of functionalized hetero(poly)cyclic compounds. Carbonylation reactions.
4. Ring-opening reactions of heterocycles (4 hours). Ring-opening reactions of five-membered mono-heterocyclic rings, 1,2-dihetero and 1,3-dihetero. Reactions for the conversion of different kind of heterocycles. Mesoionic compounds.
5. Some classes of heterocyclic compounds (4 hours). Nucleosides, nucleotides, nucleic acids, -lactam antibiotics, porphyrins, phtalocyanines, indigoid dyes.
• G. Broggini, G. Zecchi, Chimica dei composti eterocicli, Zanichelli, 2017.
• J.A. Joule, K. Mills, Heterocylic Chemistry, Blackwell Science, 2000.
The teaching activities are supplied by front lections (48 hours), also including exercises. PPT slides will be used in class.
Professor is available to meet the students any day by previous appointment.