School of Chemistry, University of KwaZulu-Natal, Durban Centre CHEM 320 ORGANIC CHEMISTRY

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1 School of Chemistry, University of KwaZulu-Natal, Durban Centre CHEM 320 ORGANIC CHEMISTRY Course Structure The course comprises of 36 lectures, 12 tutorials and 12 laboratory practical sessions. Lecturers Prof. Gert Kruger (Room E Block E, Tel , and Dr. Phil Coobes (Room 68 on the 3rd Floor, Tel , Westville, Chemistry. Textbook The formal prescribed textbook for this course is: Organic Chemistry by Clayden, Greeves, Warren and Wothers, Oxford University Press, 2001 available from Campus Bookshop. Note that this text will be used extensively in the course, with tutorial questions taken directly from the text. It is thus essential that each student purchase their own copy. The other recommended textbook is P.Y. Bruice, Organic Chemistry, 4 6 th Edition, Pearson/Prentice Hall. Other organic textbooks (Hart, Craine & Hart, Morrison & Boyd, Carey & Atkins, McMurray, Streitweiser & Heathcock, Fox & Whitesell ) and earlier editions of Bruice can also be consulted. Course Assessment The Course Mark is made up as follows: Class (or DP) Mark 33%, Examination 67% The Class Mark is in turn made up as follows: 3 Class Tests 15%, 12 Laboratory Practicals 18% Class Tests There will be 3 formal class tests, written under examination conditions (including the open book test), as follows: Week 6 Test 1 Week 9 Test 2 Week 11 Openbook test on IR, MS UV and NMR There will be NO supplementary or make up tests. Students who miss tests without providing a medical certificate or otherwise satisfactory explanation will be given ZERO, which may cost them their DP s (see DP requirements below.). These should be handed to the course co-ordinator as soon as possible after returning to campus. Lectures For lecture times and venues, please see the timetable at Laboratory Practicals Laboratory practical sessions will be held on Monday afternoons in the Synthetic Teaching Laboratory at Westville, commencing at 2.10 pm. Practical manuals must be collected from the Laboratory Technician on their respective campus in the first week of lectures. Bench and locker allocations will be posted on the n/b outside the laboratory; anyone not on the list, please see the technician in charge. Closed leather shoes, laboratory coats and safety glasses must be worn in all laboratory sessions. There will be NO supplementary or make up practicals. Students who miss practicals without adequate explanation (doctor certificate) will be given ZERO for that session, which may cost them their DP s (see DP Course outline CHEM320 Organic Chemistry 3 Semester 2 1

2 requirements below). Students who are unable to attend for medical or other unavoidable reasons should give their certificates or other supporting documentation to the course co-ordinators of their respective campus. Laboratory Practical Exemptions Practical exemptions may be granted to those students who are repeating a course given by this School and who attained a sufficiently high standard of work in previous years. Students wishing to apply for practical exemption, please see the School Secretary, and fill in an application. These will then be processed and you will be informed, before the start of practicals, whether you have exemption, or are required to repeat the practical course. It is your responsibility to make sure that you either have practical exemption, or been allocated to a practical group. A subminimum of 40.0% for the Class Mark 80% attendance at Laboratory Practicals and 100% attendance at Class Tests are DP requirements. Students who fail to attend 80% of Laboratory Practicals and 100% of Class Test (for whatever reasons), or who fail to obtain the Class Mark subminimum will have their DPs refused, and will be NOT be allowed to sit the final examination. Plagiarism Plagiarism is defined as the submission or presentation of work, in any form, which is not one's own without acknowledgement of the source(s). It is an attempt to deceive the reader that the work or ideas presented are your own, whereas, in fact they are the words/ideas of others. With regard to essays, reports and dissertations, a simple rule should be used when deciding if it is necessary to acknowledge sources. If you obtain information from an outside source, that source must be acknowledged. Another rule to follow is that any direct (verbatim) quotation must be placed in quotation marks and your wording should clearly indicate that the item is not your own work and the source immediately cited. The mere inclusion of the source in a bibliography shall not be considered sufficient acknowledgement. This applies to all work contributing to assessment, including laboratory reports and projects. All assessed work must be your own individual effort. Copying of laboratory reports, for example, is plagiarism. You may share data, where appropriate, but the calculations, answers to assignment questions and the discussion of results must be your own work. Work referred to from Internet sources must also be acknowledged as above, with the web address (URL) of the source included and the date accessed. Purpose of the module: This module is designed to introduce the learner to advanced organic chemical reactions and the manner in which they occur, as well as the tools used to identify the products of reactions. Assessment criteria: Students must be able to demonstrate an understanding of organic chemical reactions by being able to write mechanisms for reactions, answer questions on the reactions and being able to predict products and identify reagents for target molecules in a test or examination. Students must also be able to identify simple organic compounds using spectroscopic means. Course outline CHEM320 Organic Chemistry 3 Semester 2 2

3 Organic Spectroscopy (Bruice Chapt 13, 14) 10L + 1 practical session (Note that this section will be examined by means of an open book test. This section will not again be examined in the final exam.) Aim: On successful completion of this unit students should have been introduced to the practice of the techniques of NMR, IR, UV/visible spectroscopy and of mass spectrometry. Students should appreciate how the techniques can be applied either individually or collectively to the elucidation of structural problems in organic chemistry and be able to use a range of spectroscopic instruments effectively. Analyse IR, UV, NMR and mass spectra to obtain knowledge of the functional groups and structures present in a simple organic molecule Assess critically the spectroscopic analyses and assignments to obtain a self-consistent structure of a simple organic molecule. : After reviewing the material covered in this section you should be able to: Understand the importance of spectroscopy in structural elucidation. Be aware of which part of the electromagnetic spectrum each type of spectroscopy originates from. Understand the fundamental principles of NMR, UV, IR and MS. Be competent in the interpretation of spectra. Understand the interaction of infrared radiation with covalent bonds. Be aware of the connection between bonds and force constants Hooke s Law. Utilise IR spectroscopy for determining presence of the functional groups. Identify different types of protons in 1 H NMR spectra by their chemical shift. Use integration to identify how many protons are within a particular signal. Understand the origin of the multiplicity, including the (N+1) rule, and be able to measure coupling constants. Interpret 13 C NMR. use the DEPT spectrum in the interpretation. Be able to identify a chromophore. Understand the Beer-Lambert Law and the significance of є. Understand the effect of conjugation. Define bathochromic (red shift), hypsochromic (blue shift), hyperchromic and hypochromic effects. Apply Woodward-Fieser Rules for calculating λ max of dienes and polyenes or conjugated carbonyl compounds. Be aware of the application of UV in the dye industry. Be aware of how M + ions are generated and how a mass spectrum is produced. Be aware of the isotope peaks and how they can be used in the calculation of molecular formulae. Understand how structures can be elucidated from fragmentation patterns. Be aware of the use of MS in drug detection. Be able to interpret combined spectra. Conformational Analysis (Claiden Chapt 18) 6L + 2T To study the shape of organic molecules in three dimensions and To appreciate that the conformation of a molecule dictates how it will react Course outline CHEM320 Organic Chemistry 3 Semester 2 3

4 After reviewing the material covered in this section you should be able to: Construct models and draw the different conformations possible for a given cycloalkane. Apply conformational analysis in determining relative stabilities of the different conformations of a cycloalkane. Draw different configurational isomers possible for a cycloalkane (cis, trans isomers), and predict which will be optically active. Use models or drawings to explain the meanings of the terms "axial bonds," "cis, trans isomers" Explain"1,3 diaxial interaction." Relate conformation to reactivity of alicyclic systems. Understand the use of locking groups such as t-butyl groups and decalins. Understand the difference in reactivity of axial and equatorial substituents in relation to nucleophilic substitution p467. Understand the need for trans coplanar arrangement in expoxidation reactions p468. Predict the product and explain the outcome of syn and anti additions to cyclic alkenes p471. Predict the product and explain the importance of mechanisms, trans-coplanar arrangements and cyclic processes. Be able to relate rates of reaction to the conformational analysis. Explain what is a bridgehead carbon p473. Use Bredt s rule to explain why some reactions are not possible. Organic Synthesis (Clayden) 7L + 2T (Chapter 26 and 27. Chapter 28 is self study) How to make new C-C bonds using carbonyl compounds (Chapt 26). How to prevent carbonyl compounds from reacting with themselves (Chapt 26). To study the reactions of carbonyl compounds as both nucleophiles and electrophiles (Chapt 27). How to ensure that the correct product is obtained from an aldol reaction (Chapt 27). To know the different methods available for aldol reactions with enolates of aldehydes, ketones and esters (Chapt 27). How to predict the outcome of an intramolecular aldol reaction (Chapt 27). To know the Claisen condensation esters reacting with enolates (Chapt 28). How to get C-alkylation and prevent O-acylation. (Chapt 28). To study enamines in acylation reactions (Chapt 28). After reviewing the material covered in this section you should be able to: (Chapt 26) use carbonyl compounds as either electrophiles or nucleophiles. Understand the considerations that affect alkylations. Apply alkylation reactions to nitriles and nitroalkanes. Know the choice of electrophile for alkylation. Know the various techniques used to create enolates of carbonyl compounds (lithium-, silyl-, aza-enolates). Apply the alkylation of β-dicarbonyl compounds. Know the problems of regioselectivity with ketone alkylation. Know how kinetically controlled enolate formation works. How Enones provide a solution to regioselectivity problems. (Chapt 27) Use the aldol reaction. Apply cross condensations. Course outline CHEM320 Organic Chemistry 3 Semester 2 4

5 Control aldol reactions with specific enol equivalents. Know various types of eolates in adol reactions (lithium-, silyl-enolates). Prepare specific enol equivalents from 1,3-dicarbonyl compounds. How to prepare enols and enolates from acid anhydrides, esters. Prepare specific enol equivalents for aldehydes. Prepare specific enol equivalents for ketones. Apply intramolecular aldol reactions. (Chapt 28) Compare the Claisen ester condensation with the aldol reaction. Identify the problems associated with acylation at the carbon (O-acelation). Apply self-condensations (Claisen, Dieckmann) to specific tasks. Apply crossed ester condensations to specific tasks. Apply the acylation of enamines to specific tasks. Determining reaction mechanisms (Clayden Chapt 41) 5L + 1T to know the basis for the Hammett correlation. to understand non-linear correlations and the Hammett equation. to be able to use kinetic evidence in correlation to the Hammett equation. After reviewing the material covered in this section you should: Know the type of reactions that exhibit Hammett behaviour (March p278, 279; Clayden p1090, ). Understand the Hammett relationship for the hydrolysis of an aromatic ester. Understand the relationship between electronic effects of substituents on the aromatic ring and the Hammett constant σ. Understand the relationship between the electronic nature of the transition state of the reaction and the Hammett constant ρ. be able to interpret equilibria and reactions with positive Hammet ρ values. Understand reactions with negative Hammet ρ values. Understand the meaning of the Hammet ρ values. Understand the correlationship between Hammett plots and the transition state of the reaction. understand non linear Hammett plots. understand the kinetic deuterium isotope effect. understand the entropy of activation. Saturated heterocycles (Clayden Chapt 42) 5L + 2T to know the basis for heterocyclic ring closure formation (Baldwin rules). to understand change of reactivity of a hetero atom when inserted in a cyclic compound. to understand why the effect of the lone pair on the hetero-atom can control the conformation of a reaction. After reviewing the material covered in this section you should know the chemistry of: Nitrogen heterocycles as nucleophiles. Ring strain in aziridines and ring opening. Course outline CHEM320 Organic Chemistry 3 Semester 2 5

6 Oxygen and Sulfur heterocycles. The anomeric effect of saturated heterocycles. Making saturated heterocycles through ring-closure reactions. Enthalpy, Entropy and the Thorpe-Ingold effect. Baldwin s rules and ring opening. Retrosynthetic analysis (Clayden Chapt 30) 5L + 1T Understanding the relationship between synthesis and retrosynthesis. Be able to think backwards. Know how to make amines and ethers. Know what synthons are. Choosing which C-C bond to make. Logical planning in enolate chemistry. After reviewing the material covered in this section you should: understand the concept of retrosynthetic analysis: synthesis backwards. be able to use disconnections to correspond to known, reliable reactions. be able to identify synthons. be able to choose a disconnection. be able to carry out 1,3 disconnections. be able to carry out C-C disconnections. be able to carry out aldol-style disconnections with N and O in a 1,3-relationship. understand the Mannich reaction. understand Natural reactivity and umpolung. be able to carry out disconnections on 1,2-difunctional groups. Course outline CHEM320 Organic Chemistry 3 Semester 2 6