Strategies in Organic Synthesis

Paper Code: 
CHY 421
Credits: 
4
Contact Hours: 
60.00
Max. Marks: 
100.00
Objective: 

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):                                                                                                                                   

COURSE

Learning outcomes (at course level)

Learning and teaching strategies

Assessment Strategies

Paper Code

Paper Title

CHY  421

Strategies in Organic Synthesis

The students will be able to-

 

CO123-plan an organic synthesis using suitable reagents to understand a range of more sophisticated approaches to synthesis (building on the knowledge from previous years) that exploit the properties of other elements (particularly phosphorous, sulphur, silicon, boron, lithium, lanthanides and certain transition metals)

CO124-apply chemistry involving main group and transition metallic reagents to the synthesis of complex organic compounds.

CO125-explain/justify the selection of one type of reagent and reaction conditions over another in terms of efficacy in relation to a particular synthetic problem.

CO126-analyze the environmental impacts of chemistry and discover the importance of Green Chemistry.

CO127-apply the green chemical sustainable tools for cleaner environment & energy.

 Interactive Lectures

 

Discussions

 

Tutorials

 

Quiz

 

Problem solving

 

Written test

 

Google Quiz

 

Assignment

 

Semester End Exam

 

14.00
Unit I: 
Oxidation Reactions

Metal-based and non-metal based oxidations of:

  1. Alkenes to alcohols/carbonyls-hydroboration-oxidation, chiral boranes, Wacker  oxidation, SeO2/ selenium oxidants, chromium based oxidation.
  2. Alkenes to epoxides (peroxides/per acids based)-Sharpless asymmetric epoxidation, Jacob-Katsuki  epoxidation, Shi epoxidation.
  3. Alkenes to diols ( manganese, osmium based)- Sharpless asymmetric dihydroxylation, Prevost reaction and Woodward modification.
  4. Ketones to ester/lactones- Baeyer- Villiger.
  5. Alcohols to carbonyls- Corey-Kim oxidation, Dess-Martin oxidation, Swern oxidation.Manganese, aluminium, hypervalent iodine and TEMPO based reagents.

 

12.00
Unit II: 
Reduction Reactions
  1. Catalytic hydrogenation (Homogeneous hydrogenation: Wilkinson, Noyori asymmetric hydrogenation, stereo and enantioselective hydroboration.
  2. Metal based reductions : Li and Na in liquid ammonia, Birch reduction, Mc Murry, acyloin formation
  3. Hydride transfer reagents.
  4. NaBH4, triacetoxyborohydride, L-selectride, K-selectride, Luche reduction; LiAlH4, DIBAL-H, and Red-Al, trialkylsilanes and trialkylstannane, Meerwein-Pondorff-Verley reduction. Clemmenson and Wolff-Kishner reduction.

 

16.00
Unit III: 
Newer Synthetic Reactions
  1. Metal  mediated  C- C and  C-X coupling reactions: Suzuki, Heck. Stille, Sonogashira cross coupling, Buchwald-Hartwig amination and Negishi, Kumada coupling reactions. Umpolung.
  2. C=C Formation Reactions: Wittig reactions and its modifications, Shapiro, Bamford-Stevens. Julia-Lythgoe olefination and Peterson’s stereoselective olefination, phosphorus, sulphur and nitrogen ylides, Stork-enamine reaction.
  3. Multicomponent Reactions: Mannich, Biginelli, Hantzsch, Passerini. Ugi reaction.
  4. Ring Formation Reactions: Pausan-Khand reaction, Bergman cyclisation,Nazarov  cyclisation.
  5. Click Chemistry: Criteria for Click reaction, Sharpless azide cycloadditions.
  6. Olefin metathesis: Shrock’s, Grubb’s 1st and 2nd generation catalyst. Grubb-Hoveyda catalyst. Olefin cross metathesis (OCM), ring closing metathesis (RCM), ring opening metathesis (ROM) and applications.

 

8.00
Unit IV: 
Organocatalysis

Definition, generic modes, classification.

Covalent organocatalysis: Secondary amines via enamine, imine, imim ion, Amidines,      guanidines , Lewis base catalysis, Nitrogen Heterocyclic Carbenes (NHC), synthesis, structure, catalysis-homo-and cross-benzoin condensation, Stetter reaction, hydrosilylation of styrenes, transesterification.

Noncovalent organocatalysis: Hydrogen bonding catalysis, thiourea based catalysts, Diols: TADDOL.

Phosphorus containing organocatalysts: Triphenylphosphine, Binol-derived phosphoric acids, cyclic diphosphazanes, phosphonates.

 

10.00
Unit V: 
Green Chemistry

Green Chemistry & sustainability, twelve principles of green chemistry, atom economy, E-factor.

Green chemistry tools:

Solvents: Types based on hazards, applications, green solvents-supercritical fluids, ionic liquids, water, solvent free solid phase reaction.

Alternative energy sources: Ultrasound, microwave, reactions at high pressure in constrained media.

Renewable sources, C1 chemistry.

Green catalysts: Types, advantages and disadvantages ,applications in organic synthesis

 

References: 
  • Organic Chemistry; First Edition; J. Clayden, N. Greeves, S. Warren and P. Wothers; Oxford University Press, 2009.
  • Advanced Organic Chemistry: Reactions, Mechanisms and Structure; Seventh Edition; J. March; John Wiley and Sons Asia Private Limited, New Delhi, 2015.
  • Advanced Organic Chemistry Part A & B; Fifth Edition; F. A. Carey and R. J. Sundberg; Springer, US, 2007.
  • A Guidebook to Mechanism in Organic Chemistry;SixthEdition;P. Sykes; Pearson Education, Delhi, 2011.
  • Reaction Mechanism in Organic Chemistry;ThirdEdition;S. M. Mukherjee and S. Singh; Macmillan India Ltd., New Delhi, 2003.
Academic Year: