ABSTRACT
Chapter 23, Section 23.3.2) • fundamentals of kinetic and thermodynamic control (Chapter 22,
Section 22.4.2) • rate of reaction (Chapter 7, Section 7.11) • activation energy and transition states (Chapter 7, Sections 7.3
and 7.6) • Lewis bases and reactions with carbonyl compounds (Chapter 6,
Section 6.5) • rotamers and conformations (Chapter 8, Section 8.1) • that conjugated dienes are molecules that contain two C=C units
connected together such that there is a continuous array of sp2 carbons (C=C-C=C) (Chapter 23, Section 23.2)
• that conjugated dienes exhibit rotation about the C-C single bond of the C=C-C=C unit, generating two major rotamers: the s-cis and the s-trans rotamers (Chapter 23, Section 23.1; Chapter 8, Section 8.1)
• that conjugate carbonyl compounds have a C=C unit directly attached to the carbon of a carbonyl (C=C-C=O) and that there are conjugated ketones, aldehydes, acids, and acid derivatives (Chapter 23, Section 23.2)
• that 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)
This chapter will discuss 1,3-dienes in a reaction with alkenes to give cyclohexene derivatives. This is a thermal reaction driven by interactions of molecular orbitals rather than ionic or polarized intermediates. In addition to the reaction of 1,3-dienes, 1,5-dienes undergo a rearrangement to a different 1,5diene in what is known as a sigmatropic rearrangement. Similarly, allyl vinyl ethers rearrange to form alkenyl aldehydes or ketones. Both of these reactions tend to give difunctional molecules as products.
