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1 Organic structures • Why we use these particular diagrams • How organic chemists name molecules in writing and in speech • What is the skeleton of an organic molecule • What is a functional group • Some abbreviations used by all organic chemists • Drawing organic molecules realistically in an easily understood style Structure of molecules ( to include simple sulfur and phosphorus compounds ) • How we know that electrons have different energies • How electrons fit into atomic orbitals • How atomic orbitals combine to make molecular orbitals • Why organic molecules have linear, planar, or tetrahedral structures • Connection between shape and electronic structure • A true system of molecular orbital energies for simple molecules • Why such rigour is not possible for typ
ical organic molecule • Predicting the locations of lone pairs and empty orbitals • Interaction between theory and experiment 2 Organic reactions • Why molecules generally don't react with each other! • Why sometimes molecules do react with each other • In chemical reactions electrons move from full to empty orbitals • Molecular shape and structure determine reactivity • Representing the movement of electrons in reactions by curly arrows Nucleophilic addition to the carbonyl group • How and why the C=O group reacts with nucleophiles • Explaining the reactivity of the C=O group using molecular orbitals and curly arrows • What sorts of molecules can be made by reactions of C=O groups • How acid or base catalysts improve the reactivity of the C=O group Declocalization and conjugation
x2022; Interaction between orbitals over many bonds • Stabilization by the sharing of electrons over molecules • Where colour comes from • Molecular shape and structure determine reactivity • Representing one aspect of structure by curly arrows • Structure of aromatic compounds Acidity, basicity, and pKa • Why some molecules are acidic and others basic • Why some acids are strong and others weak • Why some bases are strong and others weak • Estimating acidity and basicity using pH and pKa • Structure and equilibria in proton transfer reactions • Which protons in more complex molecules are more acidic • Which lone pairs in more complex molecules are more basis Using organometallic reagents to make C-C bonds • Organometallics: nucleophilic and often strongly basic
• Making organometallics from halocompounds • Making organometallics by deprotonating carbon atoms • Using organometallics to make new C-C bonds from C=O groups Nucleophilic substitution at the carbonyl (C=O) group • Nucleophilic attack followed by loss of leaving group • What makes a good nucleophile • What makes a good leaving group • This is always a tetrahedral intermediate • How to make acid derivatives • Reactivity of acid derivatives • How to make ketones from acids • How to reduce acids to alcohols Nucleophilic substitution at C=O with loss of carbonyl oxygen • Replacement of carbonyl oxygen • Acetal formation • Imine formation • Stable and unstable imines • Reductive amination Stereochemistry • Three
-dimensional shape of molecules • Molecules with mirror images • Molecules with symmetry • How to separate mirror-image molecules • Diastereoisomers • Shape and biological activity • How to draw stereochemistry Nucleophilic substitution at saturated carbon • Nucleophilic attack on saturated carbon atoms, leading to substitution reactions • How substitution at a saturated carbon atom differs from substitution at C=O • Two mechanisms of nucleophilic substitution • Intermediates and transition states in substitution reactions • How substitution reactions affect stereochemistry • What sort of nucleophiles can substitute, and what sort of leaving groups can be substituted • The sorts of molecules that can be made by substitution 3 Conformational analysis •
;If I could see a molecule, what would its three-dimensional shape (conformation) be? • What effect does a molecule's shape have on its reactions? • How single bonds are free to rotate, but spend most of their time in just two or three well-defined arrangements • How rings of atoms are usually not planar, but "puckered" • How "puckered" six-membered rings have the most well-defined arrangements of atoms • How to use the known arrangements of the atoms in a six-membered ring to predict and explain their reactions Elimination reactions • Elimination reactions • What factors favour elimination over substitution • The two important mechanisms of elimination reactions • The importance of conformation in elimination reactions • How to use eliminations to make alkenes (and alkynes) 4 Electrophili
c addition to alkenes • Reactions of simple, unconjugated alkenes with electrophiles • Converting C=C double bonds to other functional groups by electrophilic addition • How to predict which end of an unsymmetrical alkene reacts with the electrophile • Stereoselective and stereospecific reactions of alkenes • How to make alkyl halides, epoxides, alcohols, and ethers through electrophilic addition Electrophilic aromatic substitution • Phenols as aromatic enols • Benzene and alkenes compared • Activation and deactivation • Position of substitution • Competition and co-operation • Problems with some reactions Formation and reactions of enols and enolates • How carbonyl compounds exist in equilibrium with isomers called enols • How acid or base promotes the formation of enols
and their conjugate bases, enolates • How enols and enolates have inherent mucleophilic reactivity • How this reactivity can be exploited to allow the introduction of functional groups next to carbonyl groups 5 The laboratory course will cover the basic techniques of preparative chemistry which potentially includes but is not limited to- • Recrystallisation from single and mixed solvents, filtration • Determination of m.p.,m.m.p. and use of I.R. for identification • Separation of acid/base/neutral compounds using either extraction etc., use of rotary evaporator • TLC and GC for measure of purity and for following a reaction • Use of NMR • Distillation at atmospheric pressure • Chemoselective reductions of 3-nitroacetophenone • A simple oxidation reaction analysed by GC
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