211 PHC

1. 211 PHC By: Dr. Reem Al-Wabli Dr. Ebtehal Al-Abdullah Dr. Maha Al-Mutairi

2. Dr. Reem Al-Wabli Assistant Professor in Pharmaceutical Chemistry Department Office no. S69(67) ralwabli@ksu.edu.sa

3. Course Evaluation

4. Textbooks: R. Fessenden and J. Fessenden, Organic Chemistry, PWS Publishers, Latest edition. Optional reading : Joule and Smith, Heterocyclic Chemistry, Van Nostrand Reinhold, Latest edition.

5. Topics to be covered: Part I: Stereochemistry Amino acids Part II: Classes and Mechanism of reactions Part III: Heterocyclic chemistry

6. Aim of the Course The Course is Designed to Provide the Students with: Recognize the various classes and subclasses of organic compounds and how the chemical and physical properties influence their behavior. Understand the chemical reactions unique to each class or subclass of organic molecules and their role in synthetic chemistry. Recognize the different reaction mechanisms and their importance in synthesis. Understand the stereochemistry of organic molecules and the stereochemical courses of organic reactions. Understand the role of physicochemical properties, mechanisms, and stereochemistry of organic molecules in biology and pharmacy.

7. Stereochemistry

8. Lecture Contents: • Introduction to stereochemistry. • Types of isomers. • Constitutional isomers. • Stereoisomerism. • Geometrical isomer.

9. Stereochemistry Is the study of molecules on space. i.e. how atoms or groups in a molecule arranged in space relative to each other It is that part of the science which deals with structure in three dimensions Is the field of chemistry that concerned with isomerism ( stereoisomerism )

10. Isomerism A phenomenon resulting from molecules having the same molecular formula but different arrangement In space When two or more organic compounds have the same molecular formula but differ in their physical or chemical properties they are called Isomers and the phenomenon called isomerism.

11. Isomers Constitutional isomers Stereoisomers Optical isomers Conformational isomers Geometrical isomers

12. Have the same molecular formula but different connectivity Constitutional isomers eg. Ethanol & Dimethylether Same molecular formula, C2H6O But the atoms in each compound are connected differently

13. Constitutional Isomers They differ in the way their atom are connected. 1. Chain isomerism 2. Positional isomerism 3. Functional isomerism

14. Chain Isomerism Chain isomers have the same molecular formula but differ in order in which the carbon atoms are bonded. Predict:

15. Answer:

16. Positional Isomerism Position isomers have the same molecular formula but differ in the position of functional group on the carbon chain. Examples are:-

17. Predict

18. Functional Isomerism Functional isomers have the same molecular formula but different functional groups. Examples are;

19. Stereoisomerism

20. Restricted rotation' of carbon-carbon double bonds

23. Diastereoisomers are designed cis or trans according to the priority orders or sequence rules [ atomic number ]

24. Geometrical Isomers(cis & trans) cis-trans isomers result from restricted rotation Restricted rotation- caused by either double bond or by cyclic system

25. The (E, Z) system for Nomenclature of alkene Alkenes with four different substituent Which isomer is cis and which is trans?

26. E-Z systems -Mostly used in trisubstitutedand, tetrasubstituted double bonds. -To name an alkene by E-Zsystem, separate the double bond into its 2 end. -Assign priorities to groups on each C atom. -Consider each end of the C double bond. -Assign first and second priorities to substituent group

28. Priority Rules:

34. Problem 1: