REACTION MECHANISMS IN ORGANIC CHEMISTRY AND BIORGANICS
cod. 16696

Academic year 2011/12
2° year of course - First semester
Professor
Academic discipline
Chimica organica (CHIM/06)
Field
Discipline chimiche organiche
Type of training activity
Characterising
48 hours
of face-to-face activities
6 credits
hub: PARMA
course unit
in - - -

Learning objectives

The objective of the course is to give the tools for the comprehension and the discussion of the reaction mechanisms in organic chemistry

Prerequisites

Knowledge of the arguments developed in the Organic Chemistry 1 and Organic Chemistry 2 courses

Course unit content

At first the main kinetic equation will be considered together with the primary and secondary isotopic effects.
The Hammet equation (and its modifications) will be examined in order to relate the structural effects with the reactivity of the organic compounds.
Then the role of the solvent and the role of acid and basic catalysts on the reaction mechanism will be considered.
Concerning the reaction intermediates, the radical intermediates will be deeply investigated.
Finally, the intramolecular catalysis will be examined.

Full programme

Summary of the principal kinetic equations
Stoichiometry and reaction order. Reversible and consecutive reactions. Stationary State Approximation. Saturation kinetics. Parallel reactions. Primary and secondary isotopic kinetic effects.

Structural effects on the reactivity of organic compounds.
The Hammett equation and his modifications. The Yukawa-Tsuno equation. Separation of polar, resonance and steric effects. The Taft equation.

Solvent effect on the reactivity of organic compounds.
Salt effect. The Ingold solvent effect. Thermodynamic aspects of the solvent effect. Specific salvation. Donor and acceptor solvents. Solvent effect empiric parameters: Z, Et(30), Y.

Brönsted Acids and Bases and Catalysis
Acidity and basicity functions. Superacids media. Acidity and basicity scales in different solvents and in gas phase. Acid-base catalysis in bioorganic systems. Proton transfer reactions. The Brönsted relation.

Reaction intermediates and their study
Isolation, trapping and study of reaction intermediaets. Free radical classification. Free radical sources. The capto-dativo effect. Radical inhibitors. Nucleophilic and electrophilic free radicals. Organic synthesis through free radicals.

Cycle formation reactions and intramolecular catalysis
Vicinal groups participation and intramolecular catalysis. Kinetic and thermodynamic aspects of cycle formation reactions. Biomimetic catalysis. Synthetic enzyme models.

Bibliography

Eric V. Anslyn, Dennis A. Daugherty: Modern Physical Organic Chemistry, University Science Books, 2006
F.A. Carey e R.J. Sundberg Advanced Organic Chemistry 4a Edizione, Plenum Press, 2001
J. March Advanced Organic Chemistry Reactions, Mechanisms, and Structure , 5a Edizione John Wiley & Sons , 2000

Teaching methods

Oral lesson

Assessment methods and criteria

Oral examination

Other information

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