OUTLINE
INTRODUCTION
Back ground of organic spectroscopy
Spectrometry
Application of spectroscopic technique
Spectroscopic methods based on EM spectrum (VU-VIS, IR, NMR)
Approaches in solving chemical structures
IR ( INFRARED SPECTROSCOPY)
Introduction to IR
Vibrational modes in IR spectroscopy (Stretching and Bending)
Schematic representation of IR spectrometer
The IR spectrum (scale, band intensity, FGs region, Fingerprint region)
Chemical bonds vs IR absorption
Interpretation of IR spectrum
ULTRAVIOLET-VISIBLE SPECTROSCOPY (UV-VIS)
Basics of UV-vis
Terminologies
Application of UV-vis and UV maximum determination
NUCLEAR MAGNETIC RESONANCE (NMR)
Introduction to NMR (1H and 13C)
Schematic representation of NMR machine
Features leading to the NMR – phenomenon (nuclear spin state, nuclear magnetic moment, nuclear magnetic resonance)
Mechanism of absorption (Resonance): splitting of nuclear spin energy levels in applied magnetic field
1H-NMR CHEMICAL SHIFTS
Chemical shift (δ in ppm)
Factors influencing chemical shifts ( deshielding and anisotropy)
Integrations
Shielding in 1H-NMR
Factors that influence shielding (electronegativity, hybridization of adjacent atoms, acids and exchangeable protons, magnetic anisotropy, hydrogen bonding)
Chemical equivalence and number of signals
COUPLING IN 1H-NMR
Spin-spin coupling
1st Order coupling (n+1) Rule
Pascal triangle and multiplicity
Coupling constant, J
Types of nuclear coupling : homonuclear, heteronuclear
Factors influencing magnitude of coupling constant
Karplus Relationship-Dihedral Angle
Long range coupling: 4J- nJ and W-conformation (4J)
Magnetic equivalent vs symmetry in molecule
Non-equivalent protons (free rotation, locked conformation)
2nd Order spectra
NMR spectra of aromatic compounds
Homotopic, enantiotopic and diastereotopic system
Interpretation of 1H-NMR spectra: calculation of HDI (or UN); analysis of the spectrum; integration of the spectrum; determination of types of protons; identification of splitting patterns (multiplicity).
13C- SPECTROSCOPY
Basics on 13C-NMR
Interpretation of 13C-NMR
Basics and interpretation of carbon DEPT
2D NMR
2D experiments and interpretations (COSY, NOE, HETCOR, HMQC/HSQC, HMBC)
MASS SPECTROMETRY
MS spectrometer.
MS background and theory (principle operation, fragmentation detection,…)
Application of MS (determination of molecular formula)
Resolution of mass spectrometers (low and high resolution)
Isotopic effect
Calculation of relative abundance of M+1 and M+2 peaks
Common fragments of Organic compounds: (alkanes; Cycloalkanes; alkenes. Alkynes; alcohols; aldehyde and ketones:McLafferty rearrangement)
REFERENCE
1. Jones, M. Jr. (2000). Organic chemistry 2nd ed., p641-691
2. Schoffstall, A.M., Gaddis, B.A, Druelinger, M.L., (2000). Microscle and miniscale organic chemistry laboratory experiments, p., 113-180
3. Jacabsen, N.E. (2007). NMR Spectroscopy explained, Simplified theory, Applications, and Examples for organic chemistry and structural biology, A. John Willey & Sons Inc. Publications
4. Lambert, J.B., and Mazola, E.P. Nuclear Magnetic Resonance Spectroscopy. An Introduction to principles, Application, and Experimental methods, Pearson Education Inc. (eBook)
5. Wade, L.G.,Jr (1995), Organic Chemistry, 3rd ed., Prentice Hall-Hall
6. Morison R.T., and Boyd, R.N., (1987). Organic Chemistry, 5th ed., Allyn and Bacon Inc. pp. 569-631
7. Pavia,D.L.,Lampman G.M., and Kriz, G.S. (1979), Introduction to spectroscopy. Saunders College Publishing.
8. Pavia,D.L.,Lampman G.M., and Kriz, G.S. (2001), Introduction to spectroscopy, 3rd ed., Thomson Learning, Inc.
9. http://www.chemlin.net/chemistry/ir_spectrosocpy.htm ( searched October 2009)
10. http://www.chem.ucalgary/courses/351 ( searched October 2009, google search “Chapter 13: Spectroscopy”)
11. http://www.chemistry.ccsu.edu/glagovich/teaching/316/nmr/couplingbasics.html (searched July,2008)
12. Yadav, L.D.S. Organic spectroscopy
13. www2.chemistry.msu.edu/faculty/.../Spectrpy/UV-Vis/spectrum.htm
14.Basic One- and Two-Dimensional NMR Spectroscopy by H. Friebolin ; Wiley & VCH, ; 2004
15.Introduction to NMR Spectroscopy by R.J. Abraham, J. Fisher and P.Loftus; J. Wiley & Sons, 1988.
16.High Resolution NMR techniques in Organic Chemistry by T.D.W. Claridge; Pergamon, 2009.
17.http://www.kayelaby.npl.co.uk/chemistry/3_8/3_8_7.html
18.http://chem.ch.huji.ac.il/nmr/whatisnmr/whatisnmr.html [©Roy Hoffman and Yair Ozery, The Hebrew University, Revised 2009-07-20T10:57+03]
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