1. Mòdul MD2301 - Formació general; 564497 – Química orgànica i inorgànica MASTER ON DRUGS, COSMETICS AND FOOD QUALITY Dr. Antonio Delgado Universitat de Barcelona October 2009

2. Session 3 Electrophilic aromatic substitution . Benzene, substituted benzenes and their reactivity with electrophiles. Directing groups. Organic synthesis . Linear versus convergent synthesis. Protecting groups in organic synthesis. Retrosynthetic analysis. Enantiopure compounds: chemical resolution of racemates.

3. Hückel’s rule : (4n+2)  electrons delocalized (conjugated) in a cyclic system Electrophilic aromatic substitution

4. Heterocyclic aromatic systems

6. Stability of aromatic systems

10. Electrophilic aromatic substitution Halogenation

11. Electrophilic aromatic substitution Nitration

12. Electrophilic aromatic substitution Sulfonation

13. Electrophilic aromatic substitution Alkylation

15. Electrophilic aromatic substitution

16. Electrophilic aromatic substitution on benzene derivatives

25. Planning an organic synthesis Construction of the carbon skeleton Linear vs convergent synthesis Linear synthesis Convergent synthesis

26. Construction of the carbon skeleton Retrosynthetic analysis: Strategic disconnections and synthon generation Reagent Real species Synthon ( “virtual”) Ionic or radical fragment arising from a disconnection

27. Equivalence between synthons and reagents

28. Functional group transformation Reduction of carbonyl derivatives

29. Functional group protection: protecting groups in peptide synthesis: Reactivity control

30. Protecting groups in peptide synthesis Directionality in peptide bond formation

31. Stereochemical control Enantiomers and chirality

32. Enantiomers can show different biological activity

33. Resolution of racemic mixtures Chiral chromatography

34. Chemical resolution (diastereomeric salt formation)

35. An example of diastereomeric salt formation

36. Resolution of racemic mixtures Diastereomeric salt formation in “high throughput format”

37. Resolution of racemic mixtures Chiral chromatography