Syllabus (CHEMISTRY)

Course Type: MAJ-10

Semester: 6

Course Code: BCEMMAJ10C

Course Title: Organic Chemistry – IV

(L-P-Tu): 4-2-0

Credit: 6

Practical/Theory: Combined

Course Objective: COURSE OBJECTIVE OF MAJOR - 10: The syllabus of Major -10 has been designed to provide the students with in-depth knowledge of nitrogen compounds, rearrangement reactions, the logic of organic synthesis i.e, retrosynthetic analysis of organic compounds, o

Learning Outcome: COURSE OUTCOMES OF MAJOR – 10: CO- 10.1 Thorough understanding of reactions involving nitrogen compounds. CO- 10.2 Detailed study of rearrangement reactions , which includes several organic name reactions. CO- 10.3 Detailed study of

THEORY:

Nitrogen compounds (12L)

1. Amines: Aliphatic & Aromatic: preparation, separation (Hinsberg’s method)and identification of primary, secondary and tertiary amines; reaction (withmechanism): Eschweiler–Clarke methylation, diazo coupling reaction, Mannich reaction; formation and reactions of phenylenediamines, diazomethane anddiazoacetic ester.

2. Nitro compounds (aliphatic and aromatic): preparation and reaction (withmechanism): reduction under different conditions; Nef carbonyl synthesis,Henry reaction and conjugate addition of nitroalkane anion.

3. Alkylnitrile and isonitrile: preparation and reaction (with mechanism): Thorpe nitrile condensation, von Richter reaction.

4. Diazonium salts and their related compounds: reactions (with mechanism) involving replacement of diazo group; reactions: Gomberg, Meerwein, Japp-Klingermann.

Rearrangements (16L)

Mechanism with evidence and stereochemical features for the following:

1. Rearrangement to electron-deficient carbon: Wagner-Meerwein rearrangement, pinacol rearrangement, dienone-phenol; Wolff rearrangement in Arndt-Eistertsynthesis, benzil- benzilic acid rearrangement, Demjanov rearrangement, Tiffeneau–Demjanov rearrangement.

2. Rearrangement to electron-deficient nitrogen: rearrangements: Hofmann, Curtius, Lossen, Schmidt and Beckmann.

3. Rearrangement to electron-deficient oxygen: Baeyer-Villiger oxidation, Cumene hydroperoxide-phenol rearrangement and Dakin reaction.

4. Aromatic rearrangements: Migration from oxygen to ring carbon: Friesrearrangement and Claisen rearrangement.

5. Migration from nitrogen to ring carbon: Hofmann-Martius rearrangement, Fischer-Hepp rearrangement, N-azo to C-azo rearrangement, Bambergerrearrangement, Orton rearrangement and benzidine rearrangement.

6. Rearrangement reactions by green approach: Fries rearrangement, Claisen rearrangement, Beckmann rearrangement, Baeyer-Villiger oxidation.

The Logic of Organic Synthesis (12L)

1. Retrosynthetic analysis: disconnections; synthons, donor and acceptor synthons; natural reactivity and umpolung; latent polarity in bifunctional compounds:

consonant and dissonant polarity; illogical electrophiles and nucleophiles; synthetic equivalents; functional group interconversion and addition (FGI and FGA); C-C disconnections and synthesis: one-group and two-group (1,2- to 1,5-dioxygenated compounds), reconnection (1,6-dicarbonyl); protection-deprotection strategy (alcohol, amine, carbonyl, acid).

2. Strategy of ring synthesis: thermodynamic and kinetic factors; synthesis of large rings, application of high dilution technique.

3. Asymmetric synthesis: stereoselective and stereospecific reactions; diastereoselectivity and enantioselectivity (only definition); enantioselectivity, kinetically controlled MPV reduction; diastereoselectivity: addition of nucleophiles toC=O adjacent to a stereogenic centre: Felkin-Anh and Zimmermann-Traxler models.

Organic Spectroscopy (20L)

1. UV Spectroscopy: introduction; types of electronic transitions, end absorption; transition dipole moment and allowed/forbidden transitions; chromophores andauxochromes; Bathochromic and Hypsochromic shifts; intensity of absorptions (Hyper-/Hypochromic effects); application of Woodward’s Rules for calculation of λmax for the following systems: conjugated diene, α,β-unsaturated aldehydes and ketones (alicyclic, homoannular and heteroannular); extended conjugated systems (dienes, aldehydes and ketones); relative positions of λmax considering conjugative effect, steric effect, solvent effect, effect of pH; effective chromophore concentration: keto-enol systems; benzenoid transitions.

2. IR Spectroscopy: introduction; modes of molecular vibrations (fundamental and non- fundamental); IR active molecules; application of Hooke’s law, force constant; fingerprint region and its significance; effect of deuteration; overtone bands;vibrational coupling in IR; characteristic and diagnostic stretching frequencies of CH,N-H, O-H, C-O, C-N, C-X, C=C (including skeletal vibrations of aromatic compounds), C=O, C=N, N=O, C≡C, C≡N; characteristic/diagnostic bending vibrations are included; factors affecting stretching frequencies: effect of conjugation, electronic effects, mass effect, bond multiplicity, ring- size, solvent effect, H-bondingon IR absorptions; application in functional group analysis.

3. NMR Spectroscopy: introduction; nuclear spin; NMR active molecules; basic principles of Proton Magnetic Resonance; equivalent and non-equivalent protons; chemical shift and factors influencing it; ring current effect; significance of the terms: up-/downfield, shielded and deshielded protons; spin coupling and coupling constant (1st order spectra); relative intensities of first-order multiplets: Pascal’s

triangle; chemical and magnetic equivalence in NMR ; elementary idea about non first-order splitting; anisotropic effects in alkene, alkyne, aldehydes and aromatics;NMR peak area, integration; relative peak positions with coupling patterns ofcommon organic compounds (both aliphatic and benzenoid-aromatic); rapid proton exchange; interpretation of NMR spectra of simple compounds.

4. Applications of IR, UV and NMR spectroscopy for identification of simple organic molecules.

READING REFERENCES:

1. Finar, I. L. Organic Chemistry (Volume 1), Dorling Kindersley (India) Pvt. Ltd. (Pearson Education).
2. Finar, I. L. Organic Chemistry (Volume 2: Stereochemistry and the Chemistry of Natural Products), Dorling Kindersley (India) Pvt. Ltd.(Pearson Education).
3. Norman, R.O. C., Coxon, J. M. Principles of Organic Synthesis, Third Edition, Nelson Thornes, 2003.
4. Clayden, J., Greeves, N., Warren, S., Organic Chemistry, Second edition, Oxford University Press 2012.
5. Silverstein, R. M., Bassler, G. C., Morrill, T. C. Spectrometric Identification of Organic Compounds, John Wiley and Sons, INC, Fifth edition.
6. Kemp, W. Organic Spectroscopy, Palgrave.
7. Pavia, D. L. et al. Introduction to Spectroscopy, 5th Ed. Cengage Learning India Ed. (2015).
8. Dyer, J. Application of Absorption Spectroscopy of Organic Compounds, PHI Private Limited
9. March, J. Advanced Organic Chemistry, Fourth edition, Wiley.
10. Harwood, L. M., Polar Rearrangements, Oxford Chemistry Primer, Oxford University Press.
11. Bailey, Morgan, Organonitrogen Chemistry, Oxford Chemistry Primer, Oxford University Press.
12. Warren, S. Organic Synthesis the Disconnection Approach, John Wiley and Sons.
13. Warren, S., Designing Organic Synthesis, Wiley India, 2009.
14. Carruthers, W. Modern methods of Organic Synthesis, Cambridge University Press.
15. Willis, C. A., Wills, M., Organic Synthesis, Oxford Chemistry Primer, Oxford University Press.

PRACTICALS:

1. Estimation of glycine by Sörensen’s formol method.

2. Estimation of glucose by titration using Fehling’s solution.

3. Estimation of sucrose by titration using Fehling’s solution.

4. Estimation of vitamin-C (reduced).

5. Estimation of aromatic amine (aniline) by bromination (Bromate-Bromide)method.

6. Estimation of phenol by bromination (Bromate-Bromide) method.

7. Estimation of formaldehyde (Formalin).

8. Estimation of acetic acid in commercial vinegar.

REFERENCES FOR PRACTICALS:

1. Arthur, I. V. Quantitative Organic Analysis, Pearson

2. University Hand Book of Undergraduate Chemistry Experiments, edited by Mukherjee, G.N., University of Calcutta