Proton Nuclear Magnetic Resonance Spectroscopy

Save this PDF as:
 WORD  PNG  TXT  JPG

Size: px
Start display at page:

Download "Proton Nuclear Magnetic Resonance Spectroscopy"

Transcription

1 CHEM 334L Organic Chemistry Laboratory Revision 2.0 Proton Nuclear Magnetic Resonance Spectroscopy In this laboratory exercise we will learn how to use the Chemistry Department's Nuclear Magnetic Resonance (NMR) spectrometer and how to interpret the spectra obtained using this spectrometer. NMR is one of the most powerful techniques available to the organic chemist for molecular structure determination. Therefore, knowing how to obtain and interpret NMR spectra is of critical importance. The proton at the heart of the Hydrogen atom, like the electron, exhibits behavior reminiscent of a spinning top. And, like the electron, its spin is quantized; limited to the states of Up and Down. In the presence of a strong external magnetic field (H o ), the energy of the two spin states splits; the stronger the field the greater the splitting. A photon whose frequency ( = c/) is such that its energy (E photon ) matches the energy difference (E) between the spin states can be absorbed by the proton and flip the proton's spin: E = E photon = hc / where h is Planck's constant (6.626 x J sec), c is the speed of light (300 x 10 8 m/sec) and is the photon's wavelength. For magnetic fields typically employed in modern NMR spectrometers the spin state splitting is such that these photons will lie in the Radio Frequency region of the electromagnetic spectrum. Absorbance of these photons can then be detected by the spectrometer.

2 P a g e 2 Because the splitting energy depends of the size of the NMR spectrometer's magnet field, the frequency of absorbance will also depend on the machine's magnet "size." Therefore, signal absorbance is generally reported in terms of a machine independent Chemical Shift (). The chemical shift of a signal is defined as the signal's frequency "downfield" from a reference compound's signal (Tetramethylsilane, THS, (CH 3 ) 4 Si), reported in Hertz (Hz) relative to the machine's magnet "size," reported in MegaHertz (MHz): = So, if a proton's signal is 2130 Hz downfield from the TMS signal produced by a 300 MHz NMR, it would have a chemical shift value of: = = 7.1 ppm Chemical shift values have units of parts per milliom (ppm). Now, this would all be rather uninteresting if all the Hydrogen atoms in a molecule had nuclei that absorbed at exactly the same frequency; we would observe a single absorbance peak in the spectrum. However, locally, within a molecule, each Hydrogen atom will be in a different magnetic environment. This is because the electron cloud surrounding a nucleus can act like a small wire loop within which an electric current induced by the external magnetic field establishes a local magnetic field which acts in opposition to the externally established field. This local field "shields" the nucleus from the external field. Slight molecular differences then lead to slight differences in the shielding experienced by different protons within a molecule and this causes their associated NMR signals to exhibit different chemical shifts. For instance, the molecule CH 3 CCl 2 CH 2 Cl has protons in two different "magnetic" environments, CH 3 - and -CH 2 -, and so will produce a spectrum with two signals of slightly different chemical shift. The CH 3 - signal occurs at 2.23 ppm and that of -CH 2 - at 4.00 ppm.

3 P a g e 3 Introduction to Organic Chemistry, 2 nd Ed. Andrew Streitwiesser & Clayton H. Heathcock Notice also that the CH 3 - signal is "larger," has a greater area, than the -CH 2 - signal. This is because it is due to the absorbance of three protons, versus two protons for the -CH 2 - signal. Typical chemical shift values for common proton types are provided below. You should become familiar with these values.

4 P a g e 4 Finally, neighboring protons can influence the "magnetic" environment of each other via a mechanism called spin-spin coupling. Consider two neighboring protons A and B. A will observe that B can occupy its two possible spin states. Whether B is spin Up or Down will influence the spin states of A; the coupling is through the chemical bonds connecting the Hydrogen atoms. One case will cause A to absorb at a slightly higher frequency and the other a slightly lower frequency. This will lead to a splitting of A s absorbance into a doublet. If A couples to two Hydrogen atoms, then the splitting will occur again and a triplet will be observed; etc. The relative intensities of simple multiplets are: Multiplet Intensities Doublet 1:1 Triplet 1:2:1 Quartet 1:3:3:1 Quintet 1:4:6:4:1 Sextet 1:5:10:10:5:1 Septet 1:6:15:20:15:6:1 For example, the molecule CH 3 CH 2 Cl should exhibit two NMR signals. The first is due to the CH 3 - protons and will be split into a triplet due to the neighboring two protons. The other signal, due to the -CH 2 - protons, should be split into a quartet. As seen in the spectrum below, this is in fact the case:

5 P a g e 5 Introduction to Organic Chemistry, 2 nd Ed. Andrew Streitwiesser & Clayton H. Heathcock So, spectral information concerning Chemical Shift and Coupling will provide important clues about the molecular environment of each Hydrogen atom in a molecule. This information is extracted from the spectrum via: The number of NMR signals tells us how many different "types" of protons occur within the molecule. The relative intensity of an NMR signal tells us the relative number of protons of that "type" which occur within the molecule. The chemical shift of an NMR signal tells us the nature of the environment the protons find themselves in within the molecule. The splitting pattern of the NMR signal tells us about the neighboring protons within the molecule. Let us consider the following spectrum from Streitwiesser and Heathcock:

6 P a g e 6 A separate analysis of the compound producing this spectrum indicates it has the chemical formula C 2 H 4 Br 2. The spectrum exhibits two signals, indicating the molecule possesses two types of protons. The integrated areas of the signals are in a 3:1 ratio, indicating one signal (~2.25 ppm) is due to 3 protons and the other (~5.75 ppm) is due to one proton. Thus, we have signals due to CH 3 - and -CH- moieties. The signal due to the CH 3 - moiety is split into a doublet, indicating it neighbors a -CH- moiety. The signal due to the -CH- moiety is split into a quartet, indicating it neighbors a -CH 3 moiety. Thus, the molecular structure that produced this spectrum should be: CH 3 -CHBr 2. In this way, NMR spectra can be used to elucidate molecular structure. The Department's NMR is a Bruker 400 MHz machne, similar to the one pictured below. Sample Insertion Pt. Liquid N 2 Fill Port Liquid N 2 Dewar Surrounding the Electromagnet ( The magnetic field in which the sample is inserted is generated by a 400 MHz superconducting solenoid. The solenoid is cooled in liquid He jacketed with a liquid Nitrogen dewar such that a sufficiently low temperature can be achieved to allow the windings of the solenoid to exhibit superconductivity. This electromagnet is capable of producing very large magnetic fields, thereby increasing the resolution of the instrument significantly. A solution of the sample is placed in a small glass tube and is inserted into the magnet. It is then pulsed with RF radiation and the resulting signal is Fourier Transformed into the type of spectrum we have been examining.

7 P a g e 7 In this lab exercise, you will obtain and examine the spectra of some simple compounds. You will then be asked to correlate the spectral peaks with the Hydrogen atoms in the molecules of these compounds. You should become familiar with how to interpret NMR spectra in terms of molecular structure.

8 P a g e 8 Procedure Your laboratory instructor will demonstrate how to: prepare a sample for NMR analysis. take an NMR spectrum. Special Deuterated solvents are available with which solutions of your compounds can be prepared. The deuterated solvent with then interfere with the proton NMR spectrum minimally. These solvents typically come with the TMS reference already added. You will be expected to master the use of the Department's spectrometer such that you can independently take spectra without assistance. Each person in the laboratory class should take the spectrum of one of the following compounds: Ethyl Amine t-butyl Chloride Ethyl Benzoate p-bromo Toluene 2-Bromo Butane 1,2-Dichloro Ethane Then, as a class, you should collectively assign all the peaks in each spectrum to the Hydrogen atoms of the molecules comprising the compounds.

Used to determine relative location of atoms within a molecule Most helpful spectroscopic technique in organic chemistry Related to MRI in medicine

Used to determine relative location of atoms within a molecule Most helpful spectroscopic technique in organic chemistry Related to MRI in medicine Structure Determination: Nuclear Magnetic Resonance CHEM 241 UNIT 5C 1 The Use of NMR Spectroscopy Used to determine relative location of atoms within a molecule Most helpful spectroscopic technique in

More information

Nuclear Magnetic Resonance Spectroscopy

Nuclear Magnetic Resonance Spectroscopy Nuclear Magnetic Resonance Spectroscopy Nuclear magnetic resonance spectroscopy is a powerful analytical technique used to characterize organic molecules by identifying carbonhydrogen frameworks within

More information

NMR Spectroscopy. Introduction

NMR Spectroscopy. Introduction Introduction NMR Spectroscopy Over the past fifty years nuclear magnetic resonance spectroscopy, commonly referred to as nmr, has become the most important technique for determining the structure of organic

More information

Organic Chemistry Tenth Edition

Organic Chemistry Tenth Edition Organic Chemistry Tenth Edition T. W. Graham Solomons Craig B. Fryhle Welcome to CHM 22 Organic Chemisty II Chapters 2 (IR), 9, 3-20. Chapter 2 and Chapter 9 Spectroscopy (interaction of molecule with

More information

By far the most important and useful technique to identify organic molecules. Often the only technique necessary.

By far the most important and useful technique to identify organic molecules. Often the only technique necessary. Chapter 13: NMR Spectroscopy 39 NMR Spectroscopy By far the most important and useful technique to identify organic molecules. Often the only technique necessary. NMR spectrum can be recorded for many

More information

PROTON NUCLEAR MAGNETIC RESONANCE SPECTROSCOPY (H-NMR)

PROTON NUCLEAR MAGNETIC RESONANCE SPECTROSCOPY (H-NMR) PROTON NUCLEAR MAGNETIC RESONANCE SPECTROSCOPY (H-NMR) WHAT IS H-NMR SPECTROSCOPY? References: Bruice 14.1, 14.2 Introduction NMR or nuclear magnetic resonance spectroscopy is a technique used to determine

More information

Chapter 13 Nuclear Magnetic Resonance Spectroscopy

Chapter 13 Nuclear Magnetic Resonance Spectroscopy Organic Chemistry, 6 th Edition L. G. Wade, Jr. Chapter 13 Nuclear Magnetic Resonance Spectroscopy Jo Blackburn Richland College, Dallas, TX Dallas County Community College District 2006, Prentice Hall

More information

Determination of Equilibrium Constants using NMR Spectrscopy

Determination of Equilibrium Constants using NMR Spectrscopy CHEM 331L Physical Chemistry Laboratory Revision 1.0 Determination of Equilibrium Constants using NMR Spectrscopy In this laboratory exercise we will measure a chemical equilibrium constant using key proton

More information

Nuclear Magnetic Resonance Spectroscopy

Nuclear Magnetic Resonance Spectroscopy Nuclear Magnetic Resonance Spectroscopy Introduction NMR is the most powerful tool available for organic structure determination. It is used to study a wide variety of nuclei: 1 H 13 C 15 N 19 F 31 P 2

More information

Proton Nuclear Magnetic Resonance Spectroscopy

Proton Nuclear Magnetic Resonance Spectroscopy Proton Nuclear Magnetic Resonance Spectroscopy Introduction: The NMR Spectrum serves as a great resource in determining the structure of an organic compound by revealing the hydrogen and carbon skeleton.

More information

H NMR (proton NMR): determines number and type of H atoms 13. C NMR (proton NMR): determines number and type of C atoms

H NMR (proton NMR): determines number and type of H atoms 13. C NMR (proton NMR): determines number and type of C atoms 14.1 An Introduction to NMR Spectroscopy A. The Basics of Nuclear Magnetic Resonance (NMR) Spectroscopy nuclei with odd atomic number have a S = ½ with two spin states (+1/2 and -1/2) 1 H NMR (proton NMR):

More information

NMR is the most powerful structure determination tool available to organic chemists.

NMR is the most powerful structure determination tool available to organic chemists. Nuclear Magnetic esonance (NM) Spectrometry NM is the most powerful structure determination tool available to organic chemists. An NM spectrum provides information about: 1. The number of atoms of a given

More information

Chapter 16: NMR Spectroscopy (i.e., the most exciting thing on the planet)

Chapter 16: NMR Spectroscopy (i.e., the most exciting thing on the planet) Chapter 16: NMR Spectroscopy (i.e., the most exciting thing on the planet) ne day (soon), the following will make a lot of sense to you: 16.1-16.3 The Proton: An Unexpected Journey NMR: Like electrons,

More information

The Four Questions to Ask While Interpreting Spectra. 1. How many different environments are there?

The Four Questions to Ask While Interpreting Spectra. 1. How many different environments are there? 1 H NMR Spectroscopy (#1c) The technique of 1 H NMR spectroscopy is central to organic chemistry and other fields involving analysis of organic chemicals, such as forensics and environmental science. It

More information

NMR SPECTROSCOPY A N I N T R O D U C T I O N T O... Self-study booklet NUCLEAR MAGNETIC RESONANCE. 4 3 2 1 0 δ PUBLISHING

NMR SPECTROSCOPY A N I N T R O D U C T I O N T O... Self-study booklet NUCLEAR MAGNETIC RESONANCE. 4 3 2 1 0 δ PUBLISHING A N I N T R O D U T I O N T O... NMR SPETROSOPY NULEAR MAGNETI RESONANE 4 3 1 0 δ Self-study booklet PUBLISING NMR Spectroscopy NULEAR MAGNETI RESONANE SPETROSOPY Origin of Spectra Theory All nuclei possess

More information

Chapter 15 NMR Spectroscopy

Chapter 15 NMR Spectroscopy Chempocalypse Now! Chapter 15 NMR Spectroscopy Page 1 Chapter 15 NMR Spectroscopy Parts of Topics A5 and A9 from the IB HL Chemistry Curriculum A5 A.5.1 Nuclear magnetic resonance (NMR) spectrometry (2

More information

Nuclear Magnetic Resonance

Nuclear Magnetic Resonance Nuclear Magnetic Resonance NMR is probably the most useful and powerful technique for identifying and characterizing organic compounds. Felix Bloch and Edward Mills Purcell were awarded the 1952 Nobel

More information

SIGNAL SPLITTING: Why are there so many peaks all in one area? This is called signal splitting. Example: (image from Illustrated Glossary, splitting)

SIGNAL SPLITTING: Why are there so many peaks all in one area? This is called signal splitting. Example: (image from Illustrated Glossary, splitting) Proton NMR Spectroscopy: Split the signals, not your brain! Before we can understand signal splitting, we have to understand what NMR is. This tutorial will first discuss a few concepts about NMR and then

More information

Proton Nuclear Magnetic Resonance ( 1 H-NMR) Spectroscopy

Proton Nuclear Magnetic Resonance ( 1 H-NMR) Spectroscopy Proton Nuclear Magnetic Resonance ( 1 H-NMR) Spectroscopy Theory behind NMR: In the late 1940 s, physical chemists originally developed NMR spectroscopy to study different properties of atomic nuclei,

More information

Chapter 11 Structure Determination: Nuclear Magnetic Resonance Spectroscopy. Nuclear Magnetic Resonance Spectroscopy. 11.1 Nuclear Magnetic Resonance

Chapter 11 Structure Determination: Nuclear Magnetic Resonance Spectroscopy. Nuclear Magnetic Resonance Spectroscopy. 11.1 Nuclear Magnetic Resonance John E. McMurry http://www.cengage.com/chemistry/mcmurry Chapter 11 Structure Determination: Nuclear Magnetic Resonance Spectroscopy 11.1 Nuclear Magnetic Resonance Spectroscopy Many atomic nuclei behave

More information

Shielding and Chemical Shift. Figure 14.3

Shielding and Chemical Shift. Figure 14.3 Shielding and Chemical Shift Figure 14.3 1 Summary of Shielding Figure 14.4 2 Shielding and Signal Position 3 Characteristic Chemical Shifts Protons in a given environment absorb in a predictable region

More information

13C NMR Spectroscopy

13C NMR Spectroscopy 13 C NMR Spectroscopy Introduction Nuclear magnetic resonance spectroscopy (NMR) is the most powerful tool available for structural determination. A nucleus with an odd number of protons, an odd number

More information

Chapter 13 Spectroscopy NMR, IR, MS, UV-Vis

Chapter 13 Spectroscopy NMR, IR, MS, UV-Vis Chapter 13 Spectroscopy NMR, IR, MS, UV-Vis Main points of the chapter 1. Hydrogen Nuclear Magnetic Resonance a. Splitting or coupling (what s next to what) b. Chemical shifts (what type is it) c. Integration

More information

NUCLEAR MAGNETIC RESONANCE SPECTROSCOPY

NUCLEAR MAGNETIC RESONANCE SPECTROSCOPY NMR Spectroscopy F34 1 NULEAR MAGNETI RESONANE SPETROSOPY Involves interaction of materials with the low-energy radiowave region of the electromagnetic spectrum Origin of Spectra Theory All nuclei possess

More information

Chemical shift = observed chemical shift in MHz/ frequency of spectrometer (MHz)

Chemical shift = observed chemical shift in MHz/ frequency of spectrometer (MHz) Chapter 4. Physical Basis of NMR Spectroscopy. Today the most widely used method for determining the structure of organic compounds is nuclear magnetic resonance (NMR) spectroscopy. NMR spectroscopy involves

More information

NUCLEAR MAGNETIC RESONANCE AND INTRODUCTION TO MASS SPECTROMETRY

NUCLEAR MAGNETIC RESONANCE AND INTRODUCTION TO MASS SPECTROMETRY NUCLEAR MAGNETIC RESNANCE AND INTRDUCTIN T MASS SPECTRMETRY A STUDENT SHULD BE ABLE T: 1. Identify and explain the processes involved in proton and carbon-13 nuclear magnetic resonance (NMR), and mass

More information

Introduction to Nuclear Magnetic Resonance Spectroscopy

Introduction to Nuclear Magnetic Resonance Spectroscopy Introduction to Nuclear Magnetic Resonance Spectroscopy Dr. Dean L. Olson, NMR Lab Director School of Chemical Sciences University of Illinois Called figures, equations, and tables are from Principles

More information

Nuclear Magnetic Resonance notes

Nuclear Magnetic Resonance notes Reminder: These notes are meant to supplement, not replace, the laboratory manual. Nuclear Magnetic Resonance notes Nuclear Magnetic Resonance (NMR) is a spectrometric technique which provides information

More information

NUCLEAR MAGNETIC RESONANCE SPECTROSCOPY

NUCLEAR MAGNETIC RESONANCE SPECTROSCOPY NUCLEAR MAGNETIC RESONANCE SPECTROSCOPY PRINCIPLE AND APPLICATION IN STRUCTURE ELUCIDATION Professor S. SANKARARAMAN Department of Chemistry Indian Institute of Technology Madras Chennai 600 036 sanka@iitm.ac.in

More information

Signal Manipulation. time domain NMR signal in MHz range is converted to khz (audio) range by mixing with the reference ( carrier ) frequency

Signal Manipulation. time domain NMR signal in MHz range is converted to khz (audio) range by mixing with the reference ( carrier ) frequency NMR Spectroscopy: 3 Signal Manipulation time domain NMR signal in MHz range is converted to khz (audio) range by mixing with the reference ( carrier ) frequency Ref in (MHz) mixer Signal in (MHz) Signal

More information

Chemistry 307 Chapter 10 Nuclear Magnetic Resonance

Chemistry 307 Chapter 10 Nuclear Magnetic Resonance Chemistry 307 Chapter 10 Nuclear Magnetic Resonance Nuclear magnetic resonance (NMR) spectroscopy is one of three spectroscopic techniques that are useful tools for determining the structures of organic

More information

NMR - Basic principles

NMR - Basic principles NMR - Basic principles Subatomic particles like electrons, protons and neutrons are associated with spin - a fundamental property like charge or mass. In the case of nuclei with even number of protons

More information

Organic Chemistry Nuclear Magnetic Resonance H. D. Roth. Chemistry 307 Chapter 13 Nuclear Magnetic Resonance

Organic Chemistry Nuclear Magnetic Resonance H. D. Roth. Chemistry 307 Chapter 13 Nuclear Magnetic Resonance Chemistry 307 Chapter 13 Nuclear Magnetic Resonance Nuclear magnetic resonance (NMR) spectroscopy is one of three spectroscopic techniques that are useful tools for determining the structures of organic

More information

How to Report NMR Spectra in a Formal Report

How to Report NMR Spectra in a Formal Report How to Report NMR Spectra in a Formal Report Chem7L Spring 007 ne of the most important elements of authoring an experimental publication is the correct reporting of analytical data. In Experiment, you

More information

Nuclear Magnetic Resonance (NMR) Wade Textbook

Nuclear Magnetic Resonance (NMR) Wade Textbook Nuclear Magnetic Resonance (NMR) Wade Textbook Background Is a nondestructive structural analysis technique Has the same theoretical basis as magnetic resonance imaging (MRI) Referring to MRI as nuclear

More information

Nuclear Magnetic Resonance Spectroscopy (NMR)

Nuclear Magnetic Resonance Spectroscopy (NMR) Nuclear Magnetic Resonance Spectroscopy (NMR) NMR is a spectroscopic technique which relies on the magnetic properties of the atomic nucleus. When placed in a strong magnetic field, certain nuclei resonate

More information

4. It is possible to excite, or flip the nuclear magnetic vector from the α-state to the β-state by bridging the energy gap between the two. This is a

4. It is possible to excite, or flip the nuclear magnetic vector from the α-state to the β-state by bridging the energy gap between the two. This is a BASIC PRINCIPLES INTRODUCTION TO NUCLEAR MAGNETIC RESONANCE (NMR) 1. The nuclei of certain atoms with odd atomic number, and/or odd mass behave as spinning charges. The nucleus is the center of positive

More information

1 H NMR and 13 C NMR spectra interpretation

1 H NMR and 13 C NMR spectra interpretation 1 NMR and 13 C NMR spectra interpretation Ewa Dudziak Introduction Nuclear Magnetic Resonance (NMR) spectroscopy is a powerful method for organic molecule structure determination. Moreover, NMR allows

More information

Nuclear Magnetic Resonance Spectroscopy

Nuclear Magnetic Resonance Spectroscopy Chapter 8 Nuclear Magnetic Resonance Spectroscopy http://www.yteach.co.uk/page.php/resources/view_all?id=nuclear_magnetic _resonance_nmr_spectroscopy_spin_spectrometer_spectrum_proton_t_pag e_5&from=search

More information

NMR Phenomenon. Nuclear Magnetic Resonance. µ A spinning charged particle generates a magnetic field.

NMR Phenomenon. Nuclear Magnetic Resonance. µ A spinning charged particle generates a magnetic field. NMR Phenomenon Nuclear Magnetic Resonance µ A spinning charged particle generates a magnetic field. A nucleus with a spin angular momentum will generate a magnetic moment (μ). If these tiny magnets are

More information

Nuclear Shielding and 1. H Chemical Shifts. 1 H NMR Spectroscopy Nuclear Magnetic Resonance

Nuclear Shielding and 1. H Chemical Shifts. 1 H NMR Spectroscopy Nuclear Magnetic Resonance NMR Spectroscopy Nuclear Magnetic Resonance Nuclear Shielding and hemical Shifts What do we mean by "shielding?" What do we mean by "chemical shift?" The electrons surrounding a nucleus affect the effective

More information

Examination of Proton NMR Spectra

Examination of Proton NMR Spectra Examination of Proton NMR Spectra What to Look For 1) Number of Signals --- indicates how many "different kinds" of protons are present. 2) Positions of the Signals --- indicates something about magnetic

More information

Chemical Shift (δ) 0 (by definition) 0.8-1.0 1.2-1.4 1.4-1.7 1.6-2.6 2.0-3.0 2.2-2.5 2.3-2.8 0.5-6.0 3.4-4.0 3.3-4.0 0.5-5.0

Chemical Shift (δ) 0 (by definition) 0.8-1.0 1.2-1.4 1.4-1.7 1.6-2.6 2.0-3.0 2.2-2.5 2.3-2.8 0.5-6.0 3.4-4.0 3.3-4.0 0.5-5.0 Chemical Shifts 1 H-NMR Type of Hydrogen (CH 3 ) 4 Si RCH 3 RCH 2 R R 3 CH R 2 C=CRCHR 2 RC CH ArCH 3 ArCH 2 R ROH RCH 2 OH RCH 2 OR R 2 NH O RCCH 3 O RCCH 2 R Chemical Shift (δ) 0 (by definition) 0.8-1.0

More information

CHEMISTRY 251 Spectroscopy Problems

CHEMISTRY 251 Spectroscopy Problems EMISTRY 251 Spectroscopy Problems The IR below is most likely of a: aldehyde alkane alkene alkyl bromide alkyne The IR below is most likely of a: acyl chloride alcohol 3 amide ether nitrile The IR spectrum

More information

Introduction to Quantum Mechanics and Multiplet Splitting in 1 H NMR Spectrum: A Demonstration and Classroom Activity

Introduction to Quantum Mechanics and Multiplet Splitting in 1 H NMR Spectrum: A Demonstration and Classroom Activity Introduction to Quantum Mechanics and Multiplet Splitting in 1 H NMR Spectrum: A Demonstration and Classroom Activity John Frost Ph.D. 01/24-2014 Abstract: Quantum mechanics is an incredibly important

More information

Molecular spectroscopy III: Nuclear Magnetic Resonance (NMR)

Molecular spectroscopy III: Nuclear Magnetic Resonance (NMR) Molecular spectroscopy III: Nuclear Magnetic Resonance (NMR) Nuclear magnetic resonance (NMR) is a physical phenomenon in which magnetic nuclei in a magnetic field absorb electromagnetic radiation at a

More information

A 13 C-NMR spectrum. RF Frequency The intensity of the peak doesn t does not necessarily correlate to the number of carbons.

A 13 C-NMR spectrum. RF Frequency The intensity of the peak doesn t does not necessarily correlate to the number of carbons. 13 -NMR We can examine the nuclear magnetic properties of carbon atoms in a molecule to learn about a molecules structure. Most carbons are 12 ; 12 has an even number of protons and neutrons and cannot

More information

By submitting this essay, I attest that it is my own work, completed in accordance with University regulations. Andrew Yang

By submitting this essay, I attest that it is my own work, completed in accordance with University regulations. Andrew Yang CHEM 251L: Inorganic Chemistry Laboratory Professor Jonathan Parr By submitting this essay, I attest that it is my own work, completed in accordance with University regulations. Andrew Yang An Introduction

More information

The Hydrogen Atom Is a Magnet. http://www.seed.slb.com/en/scictr/watch/gashydrates/detecting.htm

The Hydrogen Atom Is a Magnet. http://www.seed.slb.com/en/scictr/watch/gashydrates/detecting.htm The Hydrogen Atom Is a Magnet Nuclear Magnetic Resonance Spectroscopy (NMR) Proton NMR A hydrogen nucleus can be viewed as a proton, which can be viewed as a spinning charge. As with any spinning charge,

More information

Nuclear Magnetic Resonance (NMR) Spectroscopy cont... Recommended Reading:

Nuclear Magnetic Resonance (NMR) Spectroscopy cont... Recommended Reading: Applied Spectroscopy Nuclear Magnetic Resonance (NMR) Spectroscopy cont... Recommended Reading: Banwell and McCash Chapter 7 Skoog, Holler Nieman Chapter 19 Atkins, Chapter 18 Relaxation processes We need

More information

Introduction to 1D and 2D NMR Spectroscopy (1) Basics

Introduction to 1D and 2D NMR Spectroscopy (1) Basics Introduction to 1D and 2D NMR Spectroscopy (1) Basics Lecturer: Weiguo Hu A328 Conte (7-1428) weiguoh@polysci.umass.edu October 2009 1 Content At a Glance Introduction to 1D and 2D NMR Spectroscopy Experimentation

More information

Background A nucleus with an odd atomic number or an odd mass number has a nuclear spin that can be observed by NMR spectrometers.

Background A nucleus with an odd atomic number or an odd mass number has a nuclear spin that can be observed by NMR spectrometers. NMR Spectroscopy I Reading: Wade chapter, sections -- -7 Study Problems: -, -7 Key oncepts and Skills: Given an structure, determine which protons are equivalent and which are nonequivalent, predict the

More information

NMR Spectroscopy of Aromatic Compounds (#1e)

NMR Spectroscopy of Aromatic Compounds (#1e) NMR Spectroscopy of Aromatic Compounds (#1e) 1 H NMR Spectroscopy of Aromatic Compounds Erich Hückel s study of aromaticity in the 1930s produced a set of rules for determining whether a compound is aromatic.

More information

The Experiment Some nuclei have nuclear magnetic moments; just as importantly, some do not

The Experiment Some nuclei have nuclear magnetic moments; just as importantly, some do not Chemistry 2600 Lecture Notes Chapter 15 Nuclear Magnetic Resonance Spectroscopy Page 1 of 23 Structure Determination in Organic Chemistry: NMR Spectroscopy Three main techniques are used to determine the

More information

Information contained in an NMR spectrum includes: 1. number of signals. Interpreting 1 H (Proton) NMR Spectra

Information contained in an NMR spectrum includes: 1. number of signals. Interpreting 1 H (Proton) NMR Spectra Information contained in an NMR spectrum includes: Interpreting 1 (Proton) NMR Spectra 1. number of signals 2. their intensity (as measured by area under peak) 3. splitting pattern (multiplicity) Number

More information

NMR for Organic Chemistry III

NMR for Organic Chemistry III NMR for rganic Chemistry III Lecture 1 Lecture 2 Lecture 3 Lecture 4 Recap of Key Themes from NMR II + Problems CSY + Problems HSQC + Problems HMBC and Solving Structures + Problems 1 1. Practical Aspects

More information

IV. Chemical Shifts - δ unit

IV. Chemical Shifts - δ unit Chem 215-216 W11 Notes - Dr. Masato Koreeda Date: January 5, 2011 Topic: _NMR-II page 1 of 10. IV. Chemical Shifts - δ unit Each nucleus in a molecule has a different degree of electron surrounding it.

More information

Introduction to NMR Part 1. Revised 2/19/07 Anne M. Gorham

Introduction to NMR Part 1. Revised 2/19/07 Anne M. Gorham Introduction to NMR Part 1 Revised 2/19/07 Anne M. Gorham What is an NMR? Niobium-tin-copper clad coil wound like a spool of thread. The current runs through this coil, creating the magnetic field. This

More information

Determination of Equilibrium Constants using NMR Spectroscopy

Determination of Equilibrium Constants using NMR Spectroscopy CHEM 331L Physical Chemistry Laboratory Revision 2.1 Determination of Equilibrium Constants using NMR Spectroscopy In this laboratory exercise we will measure the equilibrium constant for the cis-trans

More information

For example: (Example is from page 50 of the Thinkbook)

For example: (Example is from page 50 of the Thinkbook) SOLVING COMBINED SPECTROSCOPY PROBLEMS: Lecture Supplement: page 50-53 in Thinkbook CFQ s and PP s: page 216 241 in Thinkbook Introduction: The structure of an unknown molecule can be determined using

More information

TYPES OF INFORMATION FROM NMR SPECTRUM

TYPES OF INFORMATION FROM NMR SPECTRUM TYPES OF INFORMATION FROM NMR SPETRUM 1. Each different type of hydrogen gives a peak or group of peaks (multiplet). 2. The chemical shift (δ, in ppm) gives a clue as to the type of hydrogen generating

More information

Determination of Molecular Structure by MOLECULAR SPECTROSCOPY

Determination of Molecular Structure by MOLECULAR SPECTROSCOPY Determination of Molecular Structure by MOLEULAR SPETROSOPY hemistry 3 B.Z. Shakhashiri Fall 29 Much of what we know about molecular structure has been learned by observing and analyzing how electromagnetic

More information

Christ Church 3 rd Year: Magnetic Resonance. Reading. Topics

Christ Church 3 rd Year: Magnetic Resonance. Reading. Topics Christ Church 3 rd Year: Magnetic Resonance Reading The following sources are recommended for this tutorial: Nuclear Magnetic Resonance by P. J. Hore (Oxford Chemistry Primers). This text contains the

More information

Instrumental Lab. Nuclear Magnetic Resonance. Dr Alex J. Roche

Instrumental Lab. Nuclear Magnetic Resonance. Dr Alex J. Roche Instrumental Lab Nuclear Magnetic Resonance Dr Alex J. Roche 1 Nuclear Magnetic Resonance (NMR) Spectroscopy NMR is the most powerful analytical tool currently available to an organic chemist. NMR allows

More information

MULTIPLE CHOICE. Choose the one alternative that best completes the statement or answers the question.

MULTIPLE CHOICE. Choose the one alternative that best completes the statement or answers the question. Exam Name MULTIPLE CHOICE. Choose the one alternative that best completes the statement or answers the question. 1) Calculate the percentage of 1-chloro-2-methylbutane in the following reaction. 1) A)

More information

C NMR Spectroscopy C NMR. C Transition Energy

C NMR Spectroscopy C NMR. C Transition Energy NMR NMR Spectroscopy is the most abundant natural isotope of carbon, but has a nuclear spin I = 0, rendering it unobservable by NMR. Limited to the observation of the nucleus which constitutes only.% of

More information

Solving Spectroscopy Problems

Solving Spectroscopy Problems Solving Spectroscopy Problems The following is a detailed summary on how to solve spectroscopy problems, key terms are highlighted in bold and the definitions are from the illustrated glossary on Dr. Hardinger

More information

Department of Chemistry College of Science Sultan Qaboos University. Topics and Learning Outcomes

Department of Chemistry College of Science Sultan Qaboos University. Topics and Learning Outcomes Department of Chemistry College of Science Sultan Qaboos University Title : CHEM 3326 (Applied Spectroscopy) Credits : 3 Course Format : 2 lectures and 2 tutorials Course Text : Spectrometric Identification

More information

NMR Guidelines for ACS Journals

NMR Guidelines for ACS Journals NMR Guidelines for ACS Journals Updated December 2013 1. NMR Text (Experimental Section) 1.1 The compound must be clearly identified, for example in a header at the beginning of a) the synthetic procedure

More information

Structure Determination by NMR

Structure Determination by NMR Structure Determination by NMR * Introduction to NMR * 2D NMR, resonance assignments J Correlated Based Experiments * COSY - Correlated Spectroscopy * NOESY - Nuclear Overhauser Effect Spectroscopy * HETCOR

More information

E35 SPECTROSCOPIC TECHNIQUES IN ORGANIC CHEMISTRY

E35 SPECTROSCOPIC TECHNIQUES IN ORGANIC CHEMISTRY E35 SPECTRSCPIC TECNIQUES IN RGANIC CEMISTRY TE TASK To use mass spectrometry and IR, UV/vis and NMR spectroscopy to identify organic compounds. TE SKILLS By the end of the experiment you should be able

More information

Introduction to NMR Spectroscopy and Imaging Assignment for Chapter 02: Chemical shift and J Coupling

Introduction to NMR Spectroscopy and Imaging Assignment for Chapter 02: Chemical shift and J Coupling Introduction to NMR Spectroscopy and Imaging Assignment for Chapter 02: Chemical shift and J Coupling 0. Choose the correct one(s) from the following statements or explain briefly your supporting reason

More information

NUCLEAR MAGNETIC RESONANCE SPECTROSCOPY

NUCLEAR MAGNETIC RESONANCE SPECTROSCOPY NUCLEAR MAGNETIC RESONANCE SPECTROSCOPY PRINCIPLE AND APPLICATION IN STRUCTURE ELUCIDATION Professor S. SANKARARAMAN Department of Chemistry Indian Institute of Technology Madras Chennai 600 036 sanka@iitm.ac.in

More information

Experiment #2 NUCLEAR MAGNETIC RESONANCE

Experiment #2 NUCLEAR MAGNETIC RESONANCE MASSACHUSETTS INSTITUTE OF TECHNOLOGY Department of Chemistry 5.311 Introductory Chemical Experimentation Experiment #2 NUCLEAR MAGNETIC RESONANCE I. Purpose This experiment is designed to introduce the

More information

20. NMR Spectroscopy and Magnetic Properties

20. NMR Spectroscopy and Magnetic Properties 20. NMR Spectroscopy and Magnetic Properties Nuclear Magnetic Resonance (NMR) Spectroscopy is a technique used largely by organic, inorganic, and biological chemists to determine a variety of physical

More information

NMR Nuclear Magnetic Resonance

NMR Nuclear Magnetic Resonance NMR Nuclear Magnetic Resonance Nuclear magnetic resonance (NMR) is an effect whereby magnetic nuclei in a magnetic field absorb and re-emit electromagnetic (EM) energy. This energy is at a specific resonance

More information

CHEM1002 Worksheet 4: Spectroscopy Workshop (1)

CHEM1002 Worksheet 4: Spectroscopy Workshop (1) CHEM1002 Worksheet 4: Spectroscopy Workshop (1) This worksheet forms part of the Spectroscopy Problem Solving Assignment which represents 10% of the assessment of this unit. You should use the support

More information

Interpretation of Experimental Data

Interpretation of Experimental Data Lab References When evaluating experimental data it is important to recognize what the data you are collecting is telling you, as well as the strengths and limitations of each method you are using. Additionally,

More information

1 H and 13 C NMR compared: Both give information about the number of chemically nonequivalent nuclei (nonequivalent

1 H and 13 C NMR compared: Both give information about the number of chemically nonequivalent nuclei (nonequivalent 1 H and 13 C NMR compared: 13 C NMR Spectroscopy Both give information about the number of chemically nonequivalent nuclei (nonequivalent hydrogens or nonequivalent carbons) Both give information about

More information

(3)

(3) 1. Organic compounds are often identified by using more than one analytical technique. Some of these techniques were used to identify the compounds in the following reactions. C 3 H 7 Br C 3 H 8 O C 3

More information

SHORT ANSWER. Write the word or phrase that best completes each statement or answers the question.

SHORT ANSWER. Write the word or phrase that best completes each statement or answers the question. Exam Name SHORT ANSWER. Write the word or phrase that best completes each statement or answers the question. 1) Calculate the magnetic field that corresponds to the proton resonance frequency of 300.00

More information

Introduction to Nuclear Magnetic Resonance (NMR) And. NMR Metabolomics

Introduction to Nuclear Magnetic Resonance (NMR) And. NMR Metabolomics Introduction to Nuclear Magnetic Resonance (NMR) And NMR Metabolomics Acknowledgment: Some slides from talks by Natalia Serkova, Wimal Pathmasiri, and from many internet sources (e.g., U of Oxford, Florida

More information

Chapter 13 Mass Spectrometry and Infrared Spectroscopy

Chapter 13 Mass Spectrometry and Infrared Spectroscopy Chapter 13 Mass Spectrometry and Infrared Spectroscopy Copyright 2011 The McGraw-Hill Companies, Inc. Permission required for reproduction or display. 1 Overview of Mass Spectrometry Mass spectrometry

More information

Nuclear Magnetic Resonance Spectroscopy

Nuclear Magnetic Resonance Spectroscopy Most spinning nuclei behave like magnets. Nuclear Magnetic Resonance Spectroscopy asics owever, as opposed to the behavior of a classical magnet the nuclear spin magnetic moment does not always align with

More information

NMR SPECTROSCOPY. Basic Principles, Concepts, and Applications in Chemistry. Harald Günther University of Siegen, Siegen, Germany.

NMR SPECTROSCOPY. Basic Principles, Concepts, and Applications in Chemistry. Harald Günther University of Siegen, Siegen, Germany. NMR SPECTROSCOPY Basic Principles, Concepts, and Applications in Chemistry Harald Günther University of Siegen, Siegen, Germany Second Edition Translated by Harald Günther JOHN WILEY & SONS Chichester

More information

Trans Fats. What is a trans fat? Trans fatty acids, or trans fats as they are known, are certain

Trans Fats. What is a trans fat? Trans fatty acids, or trans fats as they are known, are certain Trans Fats What is a trans fat? Trans fatty acids, or trans fats as they are known, are certain fats found in such foodstuffs as vegetable shortenings, margarines, crackers, candies baked goods and many

More information

Chapter 19 Nuclear Magnetic Resonance Spectroscopy (NMR)

Chapter 19 Nuclear Magnetic Resonance Spectroscopy (NMR) Chapter 19 Nuclear Magnetic Resonance Spectroscopy (NMR) A shorter version of the notes, designed to be covered in 4 days. Problems : 1, 2, 3, 4, 7, 10, 11, 19, 20, 22, 24, 27, 30, 34, 35 Absorption of

More information

N-phenyl-2-[(trichloroacetyl)amino]benzamide*

N-phenyl-2-[(trichloroacetyl)amino]benzamide* Asian Chemistry Letters Vol. 15, No 1 (2011) A complete 1 H and 13 C NMR data assignment for N-phenyl-2-[(trichloroacetyl)amino]benzamide* P N Penchev and J S Petrov Faculty of Chemistry, University of

More information

NMR and other Instrumental Techniques in Chemistry and the proposed National Curriculum.

NMR and other Instrumental Techniques in Chemistry and the proposed National Curriculum. NMR and other Instrumental Techniques in Chemistry and the proposed National Curriculum. Dr. John Jackowski Chair of Science, Head of Chemistry Scotch College Melbourne john.jackowski@scotch.vic.edu.au

More information

1) A compound gives a mass spectrum with peaks at m/z = 77 (40%), 112 (100%), 114 (33%), and essentially no other peaks. Identify the compound.

1) A compound gives a mass spectrum with peaks at m/z = 77 (40%), 112 (100%), 114 (33%), and essentially no other peaks. Identify the compound. 1) A compound gives a mass spectrum with peaks at m/z = 77 (40%), 112 (100%), 114 (33%), and essentially no other peaks. Identify the compound. First, your molecular ion peak is 112 and you have a M+2

More information

Using Nuclear Magnetic Resonance Spectroscopy to Identify an Unknown Compound prepared by Joseph W. LeFevre, SUNY Oswego

Using Nuclear Magnetic Resonance Spectroscopy to Identify an Unknown Compound prepared by Joseph W. LeFevre, SUNY Oswego m o d u l a r l a b o r a t o r y p r o g r a m i n c h e m i s t r y publisher:. A. Neidig organic editor: Joe Jeffers TE 711 Using Nuclear Magnetic Resonance Spectroscopy to Identify an Unknown ompound

More information

Lecture #7 (2D NMR) Utility of Resonance Assignments

Lecture #7 (2D NMR) Utility of Resonance Assignments Lecture #7 (2D NMR) Basics of multidimensional NMR (2D NMR) 2D NOESY, COSY and TOCSY 2/23/15 Utility of Resonance Assignments Resonance Assignments: Assignment of frequency positions of resonances (peaks)

More information

Introduction. Chapter 12 Mass Spectrometry and Infrared Spectroscopy. Electromagnetic Spectrum. Types of Spectroscopy 8/29/2011

Introduction. Chapter 12 Mass Spectrometry and Infrared Spectroscopy. Electromagnetic Spectrum. Types of Spectroscopy 8/29/2011 Organic Chemistry, 6 th Edition L. G. Wade, Jr. Chapter 12 Mass Spectrometry and Infrared Spectroscopy Introduction Spectroscopy is an analytical technique which helps determine structure. It destroys

More information

Nuclear Magnetic Resonance (NMR) Spectroscopy

Nuclear Magnetic Resonance (NMR) Spectroscopy April 28, 2016 Exam #3: Graded exams on Tuesday! Final Exam Tuesday, May 10 th, 10:30 a.m. Room: Votey 207 (tentative) Review Session: Sunday, May 8 th, 4 pm, Kalkin 325 (tentative) Office Hours Next week:

More information

AVANCE. Beginners Guide. Version. SGU Based Frequency Generation

AVANCE. Beginners Guide. Version. SGU Based Frequency Generation AVANCE SGU Based Frequency Generation Beginners Guide Version 001 The information in this manual may be altered without notice. BRUKER accepts no responsibility for actions taken as a result of use of

More information

Assume MAS on powders for all problems, unless stated otherwise (or obvious from the context). Calculation Exercise #1 (Wednesday)

Assume MAS on powders for all problems, unless stated otherwise (or obvious from the context). Calculation Exercise #1 (Wednesday) Exercises for Solid-State NMR Spectroscopy in Materials Chemistry Mattias Edén, Department of Materials and Environmental Chemistry, Stockholm University Assume MAS on powders for all problems, unless

More information

Determination of pk a using NMR spectroscopy

Determination of pk a using NMR spectroscopy Determination of pk a using NMR spectroscopy Objectives: 1. ecome familiar with how to collect and analyze data with the NMR 2. Understand why peaks in the NMR spectrum shift as the ph is changed 3. Understand

More information

CHAPTER 12 INFRARED SPECTROSCOPY. and MASS SPECTROSCOPY

CHAPTER 12 INFRARED SPECTROSCOPY. and MASS SPECTROSCOPY KOT 222 ORGANIC CHEMISTRY II CHAPTER 12 INFRARED SPECTROSCOPY and MASS SPECTROSCOPY Part I Infrared Spectroscopy What is Spectroscopy? Spectroscopy is the study of the interaction of matter and electromagnetic

More information

1 Introduction to NMR Spectroscopy

1 Introduction to NMR Spectroscopy Introduction to NMR Spectroscopy Tremendous progress has been made in NMR spectroscopy with the introduction of multidimensional NMR spectroscopy and pulse Fourier transform NMR spectroscopy. For a deeper

More information

Spectroscopy in Inorganic Chemistry (Theory)

Spectroscopy in Inorganic Chemistry (Theory) 1 Introduction Spectroscopy in Inorganic Chemistry (Theory) Spectroscopy is the study of the interaction of electromagnetic radiation with matter. Spectroscopy has many applications in the modern world,

More information