Environmental Sciences

Introduction. Classification of acids and bases according to Arrhenius, Brønsted-Lowry and Lewis. Acidity scale. Factors determining the strength of Brønsted-Lowry acids and bases: hybridisation, polarizability, electronegativity, inductive effect, resonance, hydrogen bond, solvent effect. Reaction mechanisms: reagents, products, intermediates and activated complexes. Kinetic and non-kinetic evidence (overview). [2 hours] Alkanes and cycloalkanes. Nomenclature, hybridization, structural isomers, conformation of linear and cyclic alkanes, bond angle. Heat of combustion and ring strain. Relationship between structure and physical properties. Newman projections. Reactions: combustion and radical halogenation (overview) [2 hours] Alkenes. Nomenclature, hybridization, stability, geometric isomers. E-Z nomenclature. Relationship between structure and physical properties. Reactions: ionic addition of hydracids (structure and stability of carbocations, Markovnikov’s Rule and Hammond’s postulate), addition of water, and halogens, epoxidation (reaction with peracids, overview). Hydroboration-oxidation, transition-metal-catalysed hydrogenation and heat of hydrogenation (overview). [4 hours] Alkynes. Nomenclature, hybridization and structure. Reactions: Pd-catalysed hydrogen addition (overview), addition of hydracids, halogens, water (H2SO4 and mercury salts as catalysts, overview), acidity of terminal alkynes (addition and nuclephilic substitution). [2 hours] Stereoisomerism. Chirality. Stereogenic centers. Enantiomers and diastereomers. Meso forms. Elements of symmetry: center of symmetry, axis of symmetry, plane of symmetry. Nomenclature of enantiomers: the R-S system (Cahn, Ingold, and Prelog). Optical activity. Racemates. Specific rotatory power. Enantiomeric excess. Fischer projections. [4 hours] Alkyl halides. Structure and physical properties. Nomenclature. Aliphatic nucleophilic substitution: SN1 and SN2 limiting mechanisms. Kinetic and non-kinetic evidence. Stereochemistry. Factors affecting reactivity (substrate, nucleophile, leaving group, solvent). Competition between SN1 and SN2 mechanisms. Beta-elimination. E1: mechanism, regiochemistry (Zaitsev’s rule). E2: mechanism, regiochemistry, stereochemistry. E2 reactions in cyclohexane systems. Competition between E1 and E2: effect of alkyl halide structure, solvent, and base. Competition between substitution and elimination: competition between SN1 and E1, competition between SN2 and E2 (effect of substrate, nucleophile/base, solvent). E1cb mechanism (overview). [4 hours] Alcohols. Nomenclature, physical properties. Reactions of alcohols: acid-base properties. Functional group transformations: reaction with hydrogen halides, thionyl chloride, phosphorus halides, and tosyl chloride (overview). Oxidation to carbonyl and carboxylic compounds (general mechanism of chromic acid oxidation; use of pyridinium chlorochromate); dehydration of alcohols. Protection (overview). [2 hours] Ethers and epoxides. Nomenclature. Reactions of ethers: acid-catalyzed cleavage with HX. Epoxides: nomenclature, opening of epoxides (acid-catalyzed and nucleophilic). Crown ethers. [1 hour] Aldehydes and ketones. Nomenclature. Addition reactions: reaction with boron and aluminum hydrides, terminal alkynes, organomagnesium reagents, water, alcohols (acetals as protecting groups). Addition-elimination reactions: reaction with primary and secondary amines. Keto-enol tautomerism in acidic and basic environments. Factors influencing keto-enol equilibrium. Aldol condensation, crossed aldol condensation. [6 hours] Carboxylic acids. Nomenclature, physical properties. Reactions of carboxylic acids: acid-base reaction, reaction with alcohols, with LiAlH4 (overview), with SOCl2 (overview), with PBr3 (overview). [1 hour] Amines. Nomenclature. Chirality. Pyramidal inversion. Chirality of quaternary ammonium salts. Basicity of aliphatic and aromatic amines. Carbohydrates and amino acids, overview of structure and properties. [2 hours] Carboxylic acid derivatives. Acyl halides, anhydrides, esters, amides, nitriles. Nomenclature, physical properties. Reactions of derivatives: with water (acid chlorides, anhydrides, esters, amides); with alcohols (acid chlorides, anhydrides, esters); with ammonia or amines (acid chlorides, anhydrides, esters), with organomagnesium reagents (esters), with LiAlH4 (esters, amides: overview). [2 hours] Aromatic compounds. Aromaticity, anti-aromaticity, and non-aromaticity. Hückel’s rule. Aromatic ions. Benzene and aromatic heterocycles. Nomenclature. Electrophilic aromatic substitution reactions: mechanism, effect of substituents (reactivity and orientation): halogenation, nitration, sulfonation, Friedel-Crafts alkylation and acylation. Nucleophilic aromatic substitution. Phenols. [4 hours]

The student is expected to have a good command of the fundamentals of chemistry, including nomenclature, chemical reactions, stoichiometry, molecular structure, electronic structure, the valence bond model and thermodynamic state functions. Such concepts are briefly re-introduced whenever necessary. Nevertheless, their knowledge is essential to the understanding of the material.

W. H. Brown ”Chimica Organica” Ed. Edises 2023 J. Mc Murry ”Chimica Organica” Ed. Piccin 2017 T.W.G. Solomons, C.B. Fryhle ”Chimica Organica” Ed. Zanichelli 2008

Attendance is not mandatory, but strongly advised.

The written exam measures the student's ability to correctly represent organic molecules (structure and nomenclature), as well as their knowledge on the reactivity of the most common classes of organic compounds. The oral exam assesses the ability to present the course concepts clearly and to identify the connections between the various topics covered.

The course is held in the form of frontal lessons. The use of a blackboard -either a traditional, or a digital one- allows the sudents to easily take notes. Only particularly complex structures, pictures and tables are projected.