Chemistry Reference
In-Depth Information
use a base that is sufficient to deprotonate a phenolic hydroxyl group. Potassium
tert-butoxide is generally sufficient to affect this deprotonation.
The second step of this sequence, illustrated below, is a Claisen rearrangement
where the allyl group is migrated from the oxygen onto the aromatic ring. The
mechanism for the Claisen rearrangement was presented in Problem 2(d) of this
chapter.
The third step of this sequence, illustrated below, is an S
N
2 reaction between a
phenol anion and methyl iodide. The mechanism for an S
N
2 reaction was presented
in detail in Chapter 4. In this reaction it is important to use a base that is sufficient
to deprotonate a phenolic hydroxyl group. Potassium tert-butoxide is generally suf-
ficient to affect this deprotonation.
This molecule is composed of two fragments resembling structures from the above
list of compounds. These fragments are illustrated below and relate to cyclohexy-
lidine triphenylphosphorane and 3-bromo-4-acetoxycyclohexanone.
