ABSTRACT
Several fundamental reactions of conjugated dienes and conjugated carbonyl compounds were discussed in Chapter 23. is chapter will show that 1,3-dienes react with alkenes, particularly with the C=C unit of a conjugated carbonyl compound, to form cyclohexene derivatives. is reaction is classied as a [4+2]-cycloaddition, commonly known as the Diels-Alder reaction, which is one of the most important reactions in organic chemistry. e mechanism for this reaction requires another examination of molecular orbitals (MOs). It is also important to note that this reaction is not an acid-base reaction, but is a new type of reaction and of mechanism.
