Heterocyclic Chemistry

Paper Code: 
CHY- 423(B)
Credits: 
4
Contact Hours: 
60.00
Max. Marks: 
100.00
Objective: 

Course Objectives :

The course aims to provide a broad introduction to heterocyclic chemistry and its nomenclature. Emphasis is given on some important heterocyclic systems, such as aziridines, oxiranes, oxetanes, benzopyrroles, benzofurans, benzothiophenes, pyrones, diazines, triazines, thiazines, and meso-ionic heterocycles. For each group, students will be acquainted with ring synthesis, chemical properties and characteristic reactions.

 

Course Outcomes (COs):

                                                                                                                       

COURSE

Learning outcomes (at course level)

Learning and teaching strategies

Assessment Strategies

Paper Code

Paper Title

CHY 423(B)

Heterocyclic Chemistry

The students will be able to-

CO153- name the different heterocyclic compounds according to IUPAC convention

CO154-justify the stability, properties and biological activities of the prescribed heterocycles.

CO155-describe mechanisms for reactions involving heterocycles as starting materials.

 Interactive Lectures

 

Discussions

 

Tutorials

 

Quiz

 

Problem solving

PowerPoint Presentation

 

Written test

 

Google Quiz

 

Assignment

 

Semester End Exam

 

 

12.00
Unit I: 
Introduction and Nomenclature of Heterocycles
Replacement and systematic nomenclature (Hantzsch-Widman system) for monocyclic,  fused and bridged heterocycles.
 
General chemical behaviour of aromatic heterocycles, classification (structural type), criteria of aromaticity (bond lengths, ring current and chemical shifts in 1H NMR-spectra, empirical resonance energy, delocalization energy and Dewar resonance energy, diamagnetic susceptibility exaltations), heteroaromatic reactivity and tautomerism in aromatic heterocycles.
 

 

12.00
Unit II: 
Conformational Analysis of Non-aromatic Heterocycles
Strain-bond angle, torsional strains and their consequences in small ring heterocycles. Conformation of six-membered heterocycles with reference to molecular geometry, barrier to ring inversion, pyramidal inversion and 1,3-diaxial interaction, stereo-electronic effects:  anomeric and related effects, attractive interactions:  hydrogen bonding and intermolecular nucleophilic-electrophilic interactions.
 
12.00
Unit III: 
Small Ring Heterocycles
Three-membered and four membered heterocycles: synthesis and reactions of aziridines, oxiranes, thiiranes, azetidines, oxetanes and thietanes, five membered heterocycles: synthesis and reactions of different isomers of diazoles (pyrazoles, imidazoles), oxazoles, thiazoles, 1,2,4-triazole, oxadiazole, thiadiazole, 1,2,3,4-tetrazole.Porphyrins and applications.
12.00
Unit IV: 
Benzo-Fused Five-Membered Heterocycles and MesoIonic
Synthesis and reactions including medicinal applications of benzopyrroles, benzofurans and benzothiophenesMeso-ionic heterocycles: classification, chemistry of some important meso-ionic heterocycles of type-A and B and their applications. Sydnones.
 
12.00
Unit V: 
Six Membered Heterocycles
With one heteroatom: synthesis and reactions of pyrilium salts and pyrones and their comparison with pyridinium and thiopyrylium salts and pyridones; synthesis and reactions of quinolizinium and benzopyrylium salts, coumarins and chromones.
 
With two or more heteroatoms: synthesis and reactions of diazines, triazines, tetrazines and thiazines.Some important macroheterocycles.
 
 
 
Essential Readings: 
  1. Heterocyclic Chemistry Vol. I & II; First Edition; R.R. Gupta and M. Kumar; Springer (India) Pvt. Ltd., 2005.
  2. Heterocyclic Chemistry; Fourth Edition; J.A. Joule and K.Mills; Blackwell Science Ltd., London, 2000.
  3. Heterocyclic Chemistry; Third Edition; T.L. Gilchrist; Delhi: Pearson Education, 2008.
  4. An Introduction to the Chemistry of Heterocyclic Compounds; Second Edition; R.M. Acheson; New Delhi: Wiley Eastern Ltd, 1976.
  5. Contemporary Heterocyclic Chemistry; G.R. Newkome and W.W. Paudler; Wiley Interscience.
 
Academic Year: