Syllabus
Syllabus
1. Introduction: Electron flow in organic reaction mechanisms, stepwise versus concerted reactions, the description of reaction mechanisms, pushing arrows, drawing reaction mechanisms, textbooks.
2. Carbanions as reaction intermediates: The structure of carbanions, generating carbanions, stabilising and destabilising carbanions, reactivity of carbanions, enolates and their analogues.
3. Organometallics as reaction intermediates: The structure of organometallic compounds, electron bookkeeping, ligands, oxidation states, electronic configuration, bonding types, addition and dissociation of ligands, oxidative addition and reductive elimination, insertion and β-elimination, metathesis of σ-bonds, transmetallation, [2+2] cycloaddition, oxidative cyclisation, stoichiometric versus catalytic processes.
4. Carbocations as reaction intermediates: The structure of carbocations, generating carbocations, stabilising and destabilising carbocations, reactivity of carbocations, nonclassical carbocations.
5. Radicals and radical ions as reactions intermediates: Free-radical reactions, chain and nonchain reactions, structure of radicals, generating radicals, stabilising and destabilising radicals, reactivity of radicals, radical anions, radical cations.
6. Ylides, carbenes, nitrenes and arynes as reaction intermediates: The structure of ylides, carbenes, nitrenes and arynes, their generation, stabilisation, destabilisation and reactivity.
7. Pericyclic reactions: Reaction controlled by the symmetry of frontier orbitals, thermal versus photochemical reactions, electrocyclic reactions, cycloadditions, sigmatropic rearrangements, ene reactions, photochemical reactions.
8. Principles, rules, effects: Acids and bases, electron donating groups, electron withdrawing groups, leaving groups, electron sources and sinks, solvent effects, kinetic versus thermodynamic control, general rules.
9. Classification of organic reaction mechanisms: Polar reactions under basic and acidic conditions, substitution reactions, elimination reactions, addition reactions, rearrangements, isomerisation reactions, multistep (cascade, domino) reactions, catalysis and autocatalysis, chemo-, regio- and stereoselective reactions.
10. Mechanisms of selected important organic reactions: Transition metal-catalysed cross-coupling reactions, alkene metathesis and other methods for the construction of the C=C bond, additions to the polar C=X bonds, aldolisation-type reactions, alkyne cycloisomerisation, modern oxidation and reduction reactions, metallation, C-H activation, the ester and amide formation and cleavage, organocatalysis, asymmetric reactions, biorelevant reactions.
11. Methods for Investigating Organic Reaction Mechanisms: Product studies, investigation of kinetics, stereochemical considerations, isotopic labelling, determining rate equation and rate constant, detection and characterisation of intermediates, investigation of catalysis, experimental and computational tools.
Annotation
A basic goal of the course is to encourage the students to acquire basic knowledge of organic reaction mechanisms. The attention is paid to the most important processes used in modern organic synthesis emphasizing the principles of electron flow and MO theory, the role of organic reaction intermediates, and the control over chemo-, regio-, and stereoselectivity.
The course includes selected mechanistic aspects of organometallic chemistry, supramolecular chemistry, and biochemistry. The students are trained in their "arrow pushing" ability solving the reaction mechanism problems of current interest to understand, explain, and predict the most probable reaction path.