2444-120911

2444-120911 - QUIZ 9 AVG. 13.2 / 25 Stnd. Dev. FINAL. 7.2...

Info iconThis preview shows pages 1–6. Sign up to view the full content.

View Full Document Right Arrow Icon
QUIZ 9 AVG. 13.2 / 25 Stnd. Dev. 7.2 FINAL. Wed. Dec. 14. 8 am Chem. A-120 A-M except for those listed below CLAS 110 N-Z plus Merchant, Messina, Mickelson, Mil-Homens, Milner, Mironets, Mobilia, Mohamed, Moore, Moreira, Muhajir, Murray,
Background image of page 1

Info iconThis preview has intentionally blurred sections. Sign up to view the full version.

View Full DocumentRight Arrow Icon
Chapter 24. Difunctional Molecules. Pericyclic Reactions 2 • 1,3-Dienes react with alkenes, particularly with the C=C unit of a conjugated carbonyl compound, to form cyclohexene derivatives. • This is a [4+2]-cycloaddition, commonly known as the Diels- Alder reaction. • The mechanism for this reaction requires an examination of the molecular orbitals of the reactants.
Background image of page 2
To begin, you should know: 3 Nomenclature for alkenes and alkynes. (chapter 5, section 5.1, 5.3) E- and Z-isomers of alkenes. (chapter 9, section 9.4) The fundamental structure and nomenclature of dienes. (chapter 5, section 5.3 and chapter 23, section 23.1) • The fundamental structure and nomenclature of ketones or aldehydes. (chapter 5, section 5.9 and chapter15 section 15.2) • Nomenclature for conjugated carbonyl compounds. (chapter 23, section 23.2) • Structure and nomenclature for bicyclic compounds. (chapter 9, section 9.7.A) • How to assign molecular orbitals to ! -bonds. (chapter 3, section 3.4) • HOMO and LUMO molecular orbitals. (chapter 3, section 3.4 and chapter 23, section 23.3.B) • The fundamentals of kinetic and thermodynamic control. (chapter 22, section 22.4.B) • Rate of reaction. (chapter 7, section 7.11) • Activation energy and transition states. (chapter 7, sections 7.3, 7.6) • Lewis bases and reactions with carbonyl compounds. (chapter 6, section 6.5) • Rotamers and conformations. (chapter 8, section 8.1) • Conjugated dienes are molecules that contain two C=C units connected together such that there is a continuous array of sp 2 carbons (C=C-C=C). (chapter 23, section 23.2)
Background image of page 3

Info iconThis preview has intentionally blurred sections. Sign up to view the full version.

View Full DocumentRight Arrow Icon
To begin, you should know: 4 • Conjugated dienes exhibit rotation about the C-C single bond of the C=C-C=C unit, generating two major rotamers, the cisoid (s-cis) and the transoid (s-trans) rotamer. (chapter 23, section 23.1 and chapter 8, section 8.1) • Conjugate carbonyl compounds have a C=C unit directly attached to the carbon of a carbonyl (C=C-C=O). There are conjugated ketones, aldehydes, acids and acid derivatives. (chapter 23, section 23.2) When a C=C or a C=O unit is attached to a benzene ring, these are also conjugated alkenes or carbonyl derivatives. (chapter 23, section 23.1) • Stereogenic centers and enantiomers. (chapter 9, section 9.1) • Absolute configuration of stereogenic centers. (chapter 9, section 9.3) • Diastereomers. (chapter 9, section 9.5)
Background image of page 4
When completed, you should know: 5 • The thermal reaction between a conjugated diene and an alkene to give a cyclohexene derivative is a [4+2]-cycloaddition, otherwise known as a Diels- Alder reaction. The Diels-Alder reaction is driven by the energy differences between the highest occupied molecular orbital (HOMO) of the diene and the lowest unoccupied molecular orbitals (LUMO) of the alkene. Alkenes bearing an electron-withdrawing group react faster because the LUMO is lowered, making the energy difference smaller. Conversely, alkenes bearing an electron-
Background image of page 5

Info iconThis preview has intentionally blurred sections. Sign up to view the full version.

View Full DocumentRight Arrow Icon
Image of page 6
This is the end of the preview. Sign up to access the rest of the document.

This note was uploaded on 02/25/2012 for the course CHEM 244 taught by Professor Jardin,j during the Fall '08 term at UConn.

Page1 / 25

2444-120911 - QUIZ 9 AVG. 13.2 / 25 Stnd. Dev. FINAL. 7.2...

This preview shows document pages 1 - 6. Sign up to view the full document.

View Full Document Right Arrow Icon
Ask a homework question - tutors are online