Organic Chemistry Ii

During theoretical classes, the concepts of aromaticity and antiaromaticity, and the fundamental structural characteristics of aromatic carbocyclic systems (benzene and derivatives) on which is based their reactivity are illustrated. Then, the main classes of reactions such as electrophilic and nucleophilic aromatic substitution, are presented, showing in details the mechanism and scope. The main classes of aromatic compounds are described. In particular, characteristics, reactivity and synthesis of arenes and alkylarenes, naphthalene, aryl and arylaliphatic arenes, nitrogen derivatives (nitro-, nitroso-, and azocompounds, arylhydroxylamines, mono- and diarylhydrazines, aromatic amines, diazonium salts), phenols and derivatives, aldehydes and ketones, nitriles, carboxylic acids and derivatives, sulfur compounds, quinones. In the second part of the course, the most important classes of heteroaromatic compounds are described, with their structural characteristics, reactivity and synthesis. In particular, pyrrole, furan, thiophene and their benzocondensed indole, benzofuran and benzothiophene are presented, some six-member atoms heterocyclic compounds such as pyridine, quinoline and isoquinoline are described. Finally, some selected information about five-member heterocycles containing two heteroatoms such as imidazole, pyrazole and isooxazole is given.
Finally, the most representative chemical and structural characteristics of biomolecules (aminoacids, peptides/proteins and carbohydrates) will be illustrated, including their synthesis and reactivity.
The course is divided in three parts: after each part a set of interactive exercises related to the topic described are organized.
Monocyclic aromatic compounds.
Benzene: principles of aromaticity, resonance, the Hückel rule. Nomenclature. Electrophilic aromatic substitution: mechanism and orientation. Halogenation, alkylation, acylation, nitration, sulfonation. Nitro compounds. Aromatic amines: synthesis and reactivity. Diazonium salts and their industrial importance. Aryl sulfonic acids. Sulfonamides. Aromatic halogen compounds: synthesis and reactivity. Nucleophilic aromatic substitution. Phenols and phenyl ethers. Fries and Claisen rearangements. Kolbe synthesis. Reaction with formaldehyde, Reimer-Tiemann and copulation reactions. Quinones. preparation and reactivity. Oxidation and reduction of aromatic compounds. Side-chain reaction: benzyl radical and carbocation.
Polycyclic aromatic compounds.
Biphenyls and atropisomerism. Fluorene and analogs. Naphthalene: synthesis, halogenations, sulfonation, nitration and Friedel-Crafts reactions. Anthracene and phenanthrene.
Heterocyclic compounds.
Classification and nomenclature. Heteroaromaticity. Synthesis and reactivity of five-membered heterocycles: pyrrole, furan and thiophene. Indole. Pyridine: structure, synthesis and properties. Pyridine N-oxide. Nucleophilic substitution. Quinoline and isoquinoline. Examples of biologically active heterocyclic compounds: pyrimidine and purine bases, nucleotides.
Amino acids and peptides.
Alpha-amino acids: structure, nomenclature, acid-base properties, isoelectric point, titration curves, stereochemistry, separation. Synthesis and resolution of amino acids. Protecting groups. Synthesis of peptides. Solid-phase synthesis.
Carbohydrates.
Classification and nomenclature. Monosaccharides: structure, stereochemistry, Fischer projections and reactivity. Cyclic hemiacetals. Mutarotation. Formation of glycosides. Reducing sugars. Oxidation and reduction. Chain lengthening and shortening. Disaccharides (sucrose, maltose, lactose) and oligosaccharides. Protecting groups. Glycosylation reaction.