Chemistry Reference
In-Depth Information
The cation pool method can preserve
carbocations stabilized by neighbouring
heteroatoms or aromatics at low temperature
(-78°C) without decomposition. Addition of
nucleophiles to the cation pool results in
desirable nucleophilic reaction ( Figure 6.11 )
[16,17].
Figure 6.11 Nucleophilic substitution reaction
by the cation pool method
At low temperature, the viscosity of the
electrolytic solution increases and this
decreases the ionic conductivity of the solution.
Dichloromethane is a suitable solvent for the
cation pool method that has sufficient
conductivity for electrolysis. With a divided
electrolytic cell, the substrate is injected into
the anode chamber and trifluoromethane
sulfonic acid (the proton source) is injected into
the cathodic chamber to promote a sacrificial
cathodic reaction.
A variety of cation pools are successfully
generated, as shown in Figure 6.12 . The cation
pool of alkoxycarbenium ions is obtained by
anodic oxidation of α-silyl ethers at low
temperature, and the addition of allylsilanes as
carbon nucleophiles yields the desired products
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