Details of CH3104 (Autumn 2018)

Level: 5 Type: Theory Credits: 4.0

Course CodeCourse NameInstructor(s)
CH3104 Stereochemistry and asymmetric synthesis Suman De Sarkar,
Sureshkumar Devarajulu

Syllabus
Acyclic stereochemistry
Representation of molecules in
Fischer, saw horse, flying-wedge and Newman formulae and their inter translations, symmetry elements, molecular chirality. Configuration: stereogenic units
i) stereocentres: systems involving 1,2,3 centres, stereogenicity, chirotopicity.
seudoasymmetric (D/L and R/
S descriptor, threo/erythro and syn/anti nomenclatures
ii) stereoaxis: chiral axis in allenes and biphenyls, R/S
descriptor; cis/trans, syn/anti,
E/Z descriptors (for C=C, C=N). Optical activity of chiral compounds: specific rotation, optical purity (enantiomeric excess), Topicity of ligands and faces (elementary idea): Pro-R, Pro-S and Re/Si descriptors. Conformation: Conformational nomenclature, eclipsed, staggered, gauche and anti; dihedral angle, torsion angle, energy barrier of rotation, relative stability of conformers on the basis of steric effect, dipole-dipole interaction, H
-bonding etc.
Cyclic stereochemistry
Cyclic Stereochemistry: Baeyer strain theory.
Conformational analysis: cyclohexane, mono and disubstituted cyclohexane, symmetry properties and optical activity. Conformation & reactivity in cyclohexane system: elimination
(E2), rearrangement, nucleophilic substitution (SN1, SN2, NGP)
Asymmetric synthesis
Introduction to asymmetric synthesis, Basic principles of a
Symmetric synthesis-Definition of stereospecific, stereoselective, enantioselective
and diastereoselective reactions
Importance of asymmetric synthesis, conditions for an efficient asymmetric synthesis, energetic considerations, strategies for asymmetric synthesis-advantages and limitations of each strategy, analytical methods for determining enantiomeric excess. Resolving agents and resolution of racemic compounds.
Asymmetric synthesis on chiral substrate
Nucleophilic addition to
?chiral carbonyl compounds; Prediction of stereochemistry,
Crams rule and related modifications. Double stereo differentiation; matched pair and mismatched pair; examples from aldol condensation and hydroboration reactions.
Asymmetric synthesis using chiral auxiliary
Chiral auxiliaries derived from proline, camphor, menthol and
other chiral pool sources.
SAMP/RAMP hydrazines, and other pyrrolidine derivatives.
Asymmetric synthesis using chiral catalysts Asymmetric alkylation and allylation of carbonyl compounds. Asymmetric hydrogenation.
Sharpless epoxidation, dihydroxylation, amino-hy
droxylation of alkenes.

References

Course Credit Options

Sl. No.ProgrammeSemester NoCourse Choice
1 IP 1 Core
2 IP 3 Not Allowed
3 IP 5 Not Allowed
4 MR 1 Not Allowed
5 MR 3 Not Allowed
6 MS 5 Core
7 RS 1 Not Allowed
8 RS 2 Not Allowed