Explain the terms: arene and aromatic. Week 1 Explain the terms: arene and aromatic. Describe and explain the models used to describe the structure of benzene. © Pearson Education Ltd 2009 This document may have been altered from the original

Week 1 Benzene ring © Pearson Education Ltd 2009 This document may have been altered from the original

Week 1 Structure of aspirin 3 © Pearson Education Ltd 2009 This document may have been altered from the original 3

Structures of some common benzene derivatives Week 1 Structures of some common benzene derivatives © Pearson Education Ltd 2009 This document may have been altered from the original 4

Week 1 Three isomers of C7H7Br 5 © Pearson Education Ltd 2009 This document may have been altered from the original 5

Benzene is classified as a carcinogen Week 1 Benzene is classified as a carcinogen © Pearson Education Ltd 2009 This document may have been altered from the original 6

Suggested linear structure for benzene, with several double bonds Week 1 Suggested linear structure for benzene, with several double bonds © Pearson Education Ltd 2009 This document may have been altered from the original 7

Kekulé structure of benzene Week 1 Kekulé structure of benzene © Pearson Education Ltd 2009 This document may have been altered from the original 8

Review the evidence for a delocalised model of benzene. Week 1 Review the evidence for a delocalised model of benzene. © Pearson Education Ltd 2009 This document may have been altered from the original

Kekulé’s equilibrium model Week 1 Kekulé’s equilibrium model © Pearson Education Ltd 2009 This document may have been altered from the original

Hydrogenation enthalpies for cyclohexene and Kekulé’s benzene Week 1 Hydrogenation enthalpies for cyclohexene and Kekulé’s benzene © Pearson Education Ltd 2009 This document may have been altered from the original 11

Enthalpy changes for the hydrogenation of cyclohexene and benzene Week 1 Enthalpy changes for the hydrogenation of cyclohexene and benzene © Pearson Education Ltd 2009 This document may have been altered from the original 12

Week 1 Compare the Kekulé and delocalised models of benzene in terms of p-orbital overlap forming π-bonds. © Pearson Education Ltd 2009 This document may have been altered from the original

Bonding around a carbon atom in a section of a benzene ring Week 1 Bonding around a carbon atom in a section of a benzene ring © Pearson Education Ltd 2009 This document may have been altered from the original

Week 1 The delocalised structure of benzene forms when the p-orbitals overlap sideways © Pearson Education Ltd 2009 This document may have been altered from the original 15

Benzene is often represented in this way in equations and mechanisms Week 1 Benzene is often represented in this way in equations and mechanisms © Pearson Education Ltd 2009 This document may have been altered from the original 16

Week 1 Resonance hybrids of benzene (left) and the common representation of benzene (right) © Pearson Education Ltd 2009 This document may have been altered from the original 17

Week 1 A localised π-bond 18 © Pearson Education Ltd 2009 This document may have been altered from the original 18

Week 1 Describe the electrophilic substitution of arenes with concentrated nitric acid in the presence of concentrated sulfuric acid. Describe the electrophilic substitution of arenes with halogens in the presence of a suitable halogen carrier. © Pearson Education Ltd 2009 This document may have been altered from the original

Equation for the preparation of nitrobenzene Week 1 Equation for the preparation of nitrobenzene © Pearson Education Ltd 2009 This document may have been altered from the original

Preparing nitrobenzene by heating benzene Week 1 Preparing nitrobenzene by heating benzene © Pearson Education Ltd 2009 This document may have been altered from the original 21

Benzene reacts with chlorine to produce chlorobenzene Week 1 Benzene reacts with chlorine to produce chlorobenzene © Pearson Education Ltd 2009 This document may have been altered from the original 22

Equation for the preparation of bromobenzene Week 1 Equation for the preparation of bromobenzene © Pearson Education Ltd 2009 This document may have been altered from the original 23

Outline the mechanism of electrophilic substitution in arenes. Week 1 Outline the mechanism of electrophilic substitution in arenes. Outline the mechanism for the mononitration and monohalogenation of benzene. © Pearson Education Ltd 2009 This document may have been altered from the original

Electrophilic substitution in benzene Week 1 Electrophilic substitution in benzene © Pearson Education Ltd 2009 This document may have been altered from the original

Curly arrows are used to represent the movement of electron pairs Week 1 Curly arrows are used to represent the movement of electron pairs © Pearson Education Ltd 2009 This document may have been altered from the original 26

Mechanism for the nitration of benzene Week 1 Mechanism for the nitration of benzene © Pearson Education Ltd 2009 This document may have been altered from the original 27

Mechanism for the bromination of benzene Week 1 Mechanism for the bromination of benzene © Pearson Education Ltd 2009 This document may have been altered from the original 28