Synthesis &Reterosynthesis in Organic Chemistry

Paper Code: 
CHY- 321
Contact Hours: 
Max. Marks: 

Course Objectives :

The aim of the course is to give advanced knowledge in synthetic organic chemistry so that the learner can suggest alternative reagents and reactions for performing desired organic transformations. It is also aimed at making students aware of the basic principles and applications of green chemistry so that they acquire the competence to think, design and develop sustainable chemistry.

Course Outcomes (COs):



Learning outcomes (at course level)

Learning and teaching strategies

Assessment Strategies

Paper Code

Paper Title

CHY 321

Synthesis & Retrosynthesis in Organic Chemistry

The students will be able to-


CO90- appraise the metal and non-metal-based oxidation and reduction reactions from the mechanistic, stereochemistry and regiochemistry point of view.

CO91-demonstrate the use of organocatalysts specifically, Covalent, Noncovalent and Phosphorus containing organocatalysts in the synthesis of a diverse range of organic compounds

CO92- predict structures of the products based on the reaction conditions and reagents used.

CO93-justify the use of a specific organic reagent and catalyst in a particular reaction via the mechanism of the reaction

CO94- analyze the environmental impacts of chemistry and highlight the use and significance of 12 basic principles of Green Chemistry

CO95- hypothesise novel organic compounds using the newer greener sustainable technologies and methods for cleaner environment & energy

CO96- appraise the newly reported organic reactions along with the mechanisms involved in the formation of C-C, C-X, C=C bonds.

Interactive lectures






Problem solving

Written test








Group activity


Semester end examination




Unit I: 
Basics of Photochemistry and Photochemical Reactions of Carbonyl Compounds

Laws of photochemistry. Fate of excited molecules - Jablonskii diagram, intersystem crossing, energy transfer, photosensitization, quenching, quantum yield, Stern-Volmer equation. Photochemical reactions of ketones – alpha cleavage or Norrish type I cleavage, gamma hydrogen transfer or Norrish type II cleavage; photo reductions; Paterno-Buchi reactions; photochemistry of α,β-unsaturated ketones, β,γ-unsaturated ketones, cyclohexadienones (cross conjugated and conjugated).

Unit II: 
Photochemistry of Alkenes and Aromatic Compounds
Photochemistry of alkenes:intramolecular reactions of the olefinic bond – cis-trans  isomerisation (stilbene), cyclization reactions, rearrangement of 1,4 and 1,5-dienes, di-π methane rearrangement.
Photochemistry of aromatic compounds: photochemical rearrangement, photostationary state, 1, 3, 5 – trimethyl benzene to 1, 2, 4-trimethyl benzene.
Miscellaneous Photochemical Reactions: Barton reaction, photo Fries rearrangement of ethers and anilides, singlet oxygen reactions (photo oxygenation).
Unit III: 
Pericyclic Reactions -I
General characteristics, classification, molecular orbital symmetry.
Electrocyclic reactions:theories of explanation (FMO, Woodword-Hoffmann and PMO approach), frontier orbitals, electrocyclisation and reterocyclisation of 1,3 butadiene ,cyclobutadiene and ,hexatriene derivatives, allylic cations(1,5 diphenylpentadienyl cation) and  allylic anions (1,5 diphenylpentadienyl anion), ring opening in bicycle [4.1.0] heptane derivatives, valence tautomerism.
Unit IV: 
Pericyclic Reactions–II
Cycloaddtion reactions: 2+2, 4+2 cycloaddition, 1, 3-dipolar cycloaddition and cheletropic reactions; stereoselectivity (endo, exo), stereospecific and regioselective hydrogen reactions, Lewis-acid catalysis in Diels’ Alder reaction.
Sigmatropic rearrangements: suprafacial and antarafacial shifts of H, sigmatropic shifts involving carbon moieties, 3, 3- and 5, 5-sigmatropic rearrangements; Claisen, Cope and Aza-Cope rearrangements; isomerization of divinyl cyclopropane; fluxional tautomerism (bullvalene); ene reaction.
Unit V: 
Disconnection Approach in Organic Synthesis
Synthons and synthetic equivalents, disconnection approach, functional group inter-conversions, the importance of the order of events in organic synthesis, one group C-X and two group C-X disconnections, chemoselectivity, reversal of polarity, cyclisation reactions, amine synthesis; principle of protection of alcohol, amine, carbonyl and carboxyl groups.
One and Two Group C-C Disconnections:
Alcohols and carbonyl compounds, regioselectivity, alkene synthesis, uses of alkynes and aliphatic nitro compounds in organic synthesis; Diels’ Alder reaction, 1,3-difunctionalised compounds, α,β-unsaturated carbonyl compounds, control in carbonyl condensations,1,5-difunctionalised compounds,Micheal addition and Robinson annelation.
Essential Readings: 
  1. Photochemistry; Horsepool.
  2. Fundamentals of Photochemistry; Third Edition; K.K. Rohatagiand Mukherjee; New Age International Publishers Pvt. Ltd., New Delhi, 2007.
  3.  Molecular Reactions and Photochemistry; First Edition; C. H. Depuy and L. Orville  Chapman; Prentice-Hall of India Pvt. Ltd, New Delhi, 1988.
  4. Reaction Mechanism in Organic Chemistry; Third Edition; S.M. Mukherjee and S.P. Singh; Macmillan, India Ltd., New Delhi, 2003.
  5. Advanced Organic Chemistry Part A & B; Fourth Edition; F. A. Carey and R. J. Sundberg; Kluwer Academic/Plenum Publishers, New York, 2001.
  6. Designing Organic Synthesis: A Programmed Introduction to the SythonApproach; First Edition; S. Warren; John Wiley and Sons, Great Britain, 2000.
  7. Organic Synthesis- Concepts, Methods and Starting Materials; J. Fuhrhop and G.Penzillin; Wiley-Vch,New York: 2003.
  8. Modern Methods of Organic Synthesis; Fourth Edition; W. Carruthers; Cambridge Univ. Press, UK, 2005.
Academic Year: