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Cerium(III)
chloride can be used as a starting point for the preparation of other
cerium salts, such as the Lewis acid, cerium (III)
trifluoromethanesulfonate, used for Friedel-Crafts acylations. It is
also used itself as a Lewis acid, for example as a catalyst in Friedel-Crafts
alkylation reactions.
Luche reduction
of alpha, beta-unsaturated carbonyl compounds has become a popular
method in organic synthesis, where CeCl3.7H2O is
used in conjunction with sodium borohydride. For example carvone gives
only the allylic alcohol 1 and none of the saturated alcohol 2. Without
CeCl3, a mixture of 1 and 2 is formed.
Organic synthesis
is for alkylation of ketones which would otherwise form enolates if
simple organo lithium reagents were to be used. For example, compound
3 would be expected to simply form an enolate without CeCl3
being present, but in the presence of CeCl3 smooth alkylation
occurs:
Cerium (III) chloride heptahydrate CeCl3 · H2O
catalyzes enamination of β-dicarbonyl compounds with primary amines in
aqueous medium at room temperature to afford the corresponding β-enamino
ketones with high chemoselectivity.
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