Stereochemistry: chirality, prochirality, stereoisomerism – diastereoisomers, enantiomers. Optical activity, racemization resolution, absolute configuration, (R) ans (S) system (Cahn, Ingold and Prelog). Conformational studies: Ethane, propane, butane and substituted compounds; The barrier to rotation about C-C bonds, staggered and eclipsed conformers and their populations, hydrogen bonding, Van der waals and other effects. Cyclohexanes, monosubstituted and disubstituted. Stereochemical and other effects in nucleophilic substitution, elimination and addition reactions. Neighbouring group participation. Diastereoselective and enantioselective reactions such as reduction, displacement, addition, aldol and pericyclic reactions. 1,3-sigmatropic rearrangements and the stereochemistry of rearrangement reactions.