Basics of Organic Chemistry

Pre requisite: Delocalized chemical bond – conjugation, cross conjugation, resonance and field effects. hyperconjugation, tautomerism.

Aromaticity in benzenoid and non-benzenoid compounds, alternant and non-alternant hydrocarbons, Huckel’s rule and Möbius system, energy level of π molecular orbitals in simple systems (ethylene, 1, 3 butadiene, benzene and allylic system), Huckel’s theory of conjugated systems, bond order and charge density calculations, applications to ethylene, and butadiene. Annulenes, fullerenes, antiaromaticity, homoaromaticity, PMO approach, steric inhibition to resonance.

Bonds weaker than covalent – addition compounds, phase transfer catalysis and crown ether complexes, cryptands, inclusion compounds, cyclodextrins, catenanes, rotaxanes and Kekulene.

Structure and Reactivity:  Concept of linear free energy relationship-Hammett and Taft equations, application  in the determination of organic reaction mechanisms.

Hammond’s postulates, Nucleophilicity, Curtin- Hammett principle.

Pre requisite: Types of reactions, types of mechanisms, general principles for the determination of reaction mechanism.

Organic Reaction Dynamics and Reactive Intermediates: general methods for the determination of reaction mechanism – product analysis, determination of presence of intermediates, study of catalysis, isotopic labelling, stereochemical evidences, kinetic evidences and isotope effects.

Methods of generation, structure and reactivity of carbocations, carbanions, radical-anions and radical-cations, arynes, carbenes and nitrenes.

General mechanistic consideration – migratory aptitude, memory effects of the following rearrangements:

Pinacol-pinacolone rearrangement, Wagner-Meerwein rearrangement, Damjanov rearrangement, Benzil-benzilic acid rearrangement, Favorskii rearrangement, Arndt-Eistert rearrangement, Neber rearrangement, Beckmann rearrangement, Hofmann rearrangement, Curtius rearrangement, Lossen rearrangement, Schmidt rearrangement, Wolff rearrangement, Baeyer-Villiger oxidation, Shapiro reaction, Dienone- phenol rearrangement, Wittig  rearrangement.

Pre requisite: Conformation, configuration, erythro and threo isomers, E,Z and D,L nomenclature.

Optical isomerism, elements of symmetry chirality, enantiomers, diastereomers, R,S  nomenclature, absolute configuration, optical purity resolution, prochirality; enantiotopic and diastereotopic atoms, groups and faces, stereoselective and stereospecific synthesis reactions.

Pseudoasymmetry: optical activity in the absence of chiral carbons (biphenyls, allenes, spiranes, ansa compounds and cyclophanes), chirality due to helical shape; chirality in the compounds containing N, S and P.

Geometrical isomerism in cyclic and condensed systems (decalins, decalols and decalones), conformational analysis of cycloalkanes (5, 6, 7 membered rings) and decalins, effect of conformation on reactivity, conformations of sugars (glucose,maltose and sucrose), steric strain due to unavoidable crowding.

Asymmetric synthesis, Cram’s rule, Prelog’s rule, Horeau’s rule, CD, ORD, octant rule, Cotton effect and their application in determination of absolute and relative configuration and conformation, the axial haloketone rule.

Self Study - Geometrical isomerism in acyclic systems.