85
4
5 Dimer fatty acids are formed by
catalytic dimerization of two fatty
acids. By reacting the dimer fatty acids
with diamines, polyamides are formed,
which are used as adhesives (hot
melts).
5 Metathesis of unsaturated oleochemicals
has so far only been carried out on an
industrial scale in special cases, but
has great potential. Self-metathesis
of methyl oleate results in a diester;
intermolecular metathesis of two
unsaturated triglycerides results in
“dimeric triglycerides” with high viscosity
and good drying properties.
5 By cross-metathesis of methyl oleate
with ethene (the so-called ethenolysis),
methyl 9-decenoate is formed. Because
of its terminal C=C double bond, it
is a valuable starting chemical for
bifunctional compounds.
5 Ethenolysis of triglycerides can be used
to produce fats with short-chain fatty
acids. Ethenolysis of wax esters, e.g.
jojoba oil, produces α,ω-unsaturated
monoesters.
5 Cross-metatheses with asymmetric
alkenes usually lead to mixtures. Valuable
bifunctional products can be synthesized
by controlling them with the metathesis
catalyst, usually a ruthenium carbene
complex.
5 Polyunsaturated fatty acids, e.g. linoleic
acid, can undergo Diels–Alder reactions
or catalytic cooligomerizations after
isomerization to the corresponding
conjuenic acids. Cyclic or branched
products are formed which can be used,
for example, as lubricants.
5 Triple unsaturated linolenic acid can
also undergo Diels–Alder reactions, e.g.
intramolecularly with itself to form ring
molecules. The production of linoleum is
industrially important: Under the influence
of atmospheric oxygen, linolenic acid
containing linseed oil polymerizes to
form a rubber-like mass, which is then
processed with fillers and jute sheets to
form floor coverings.
5 The same applies to hydrocyanation, i.e.
the reaction of unsaturated oleochemicals
with hydrocyanic acid. This reaction is well
established in petrochemical industry: The
nickel–phosphite-catalyzed bishydrocyanation of 1,3-butadiene is carried out industrially to produce adipodinitrile, an important
intermediate for the synthesis of adipic acid
and hexamethylene diamine. A large-scale
use in oleochemistry does not yet exist.
Summary (Take-Home Messages)
5 Substitution reactions on the saturated
fatty acid alkyl chain are industrially
only used to a limited extent, as they
usually lead to complex mixtures. An
exception is the selective sulfonation
at the methylene group adjacent to
the carboxyl group: α-Estersulfonates
are produced, which have very good
surfactant properties and can be used
as substitutes for petrochemical linear
alkylbenzene sulfonates.
5 Unsaturated oleochemicals can be
transferred into the corresponding
epoxides with the aid of performic or
peracetic acid. If the epoxy rings are
opened with water, diols are formed
which are used for polyurethane
production.
5 Bishydroxylation with hydrogen peroxide
also leads directly to the vicinal diols.
5 Ozonolysis of the C = C bond of a fatty
acid produces a mono- and a diacid.
Pelargonic and azelaic acids, for instance,
are formed from oleic acid.
5 Unsaturated oleochemicals can also
be functionalized by catalytic C–C
linkages on the alkyl chain. Bifunctional
compounds are formed which are
suitable for the synthesis of polymers
(polyester, polyamides, etc.).
5 Aldehyde esters are formed by
hydroformylation, amino esters by
hydroaminomethylation. Hydrocarboxylation and alkoxycarbonylation lead
to branched dicarboxylic acids or their
esters, respectively.
4.2 · Reactions at the C = C Double Bond of Unsaturated Oleochemicals
4
5 Dimer fatty acids are formed by
catalytic dimerization of two fatty
acids. By reacting the dimer fatty acids
with diamines, polyamides are formed,
which are used as adhesives (hot
melts).
5 Metathesis of unsaturated oleochemicals
has so far only been carried out on an
industrial scale in special cases, but
has great potential. Self-metathesis
of methyl oleate results in a diester;
intermolecular metathesis of two
unsaturated triglycerides results in
“dimeric triglycerides” with high viscosity
and good drying properties.
5 By cross-metathesis of methyl oleate
with ethene (the so-called ethenolysis),
methyl 9-decenoate is formed. Because
of its terminal C=C double bond, it
is a valuable starting chemical for
bifunctional compounds.
5 Ethenolysis of triglycerides can be used
to produce fats with short-chain fatty
acids. Ethenolysis of wax esters, e.g.
jojoba oil, produces α,ω-unsaturated
monoesters.
5 Cross-metatheses with asymmetric
alkenes usually lead to mixtures. Valuable
bifunctional products can be synthesized
by controlling them with the metathesis
catalyst, usually a ruthenium carbene
complex.
5 Polyunsaturated fatty acids, e.g. linoleic
acid, can undergo Diels–Alder reactions
or catalytic cooligomerizations after
isomerization to the corresponding
conjuenic acids. Cyclic or branched
products are formed which can be used,
for example, as lubricants.
5 Triple unsaturated linolenic acid can
also undergo Diels–Alder reactions, e.g.
intramolecularly with itself to form ring
molecules. The production of linoleum is
industrially important: Under the influence
of atmospheric oxygen, linolenic acid
containing linseed oil polymerizes to
form a rubber-like mass, which is then
processed with fillers and jute sheets to
form floor coverings.
5 The same applies to hydrocyanation, i.e.
the reaction of unsaturated oleochemicals
with hydrocyanic acid. This reaction is well
established in petrochemical industry: The
nickel–phosphite-catalyzed bishydrocyanation of 1,3-butadiene is carried out industrially to produce adipodinitrile, an important
intermediate for the synthesis of adipic acid
and hexamethylene diamine. A large-scale
use in oleochemistry does not yet exist.
Summary (Take-Home Messages)
5 Substitution reactions on the saturated
fatty acid alkyl chain are industrially
only used to a limited extent, as they
usually lead to complex mixtures. An
exception is the selective sulfonation
at the methylene group adjacent to
the carboxyl group: α-Estersulfonates
are produced, which have very good
surfactant properties and can be used
as substitutes for petrochemical linear
alkylbenzene sulfonates.
5 Unsaturated oleochemicals can be
transferred into the corresponding
epoxides with the aid of performic or
peracetic acid. If the epoxy rings are
opened with water, diols are formed
which are used for polyurethane
production.
5 Bishydroxylation with hydrogen peroxide
also leads directly to the vicinal diols.
5 Ozonolysis of the C = C bond of a fatty
acid produces a mono- and a diacid.
Pelargonic and azelaic acids, for instance,
are formed from oleic acid.
5 Unsaturated oleochemicals can also
be functionalized by catalytic C–C
linkages on the alkyl chain. Bifunctional
compounds are formed which are
suitable for the synthesis of polymers
(polyester, polyamides, etc.).
5 Aldehyde esters are formed by
hydroformylation, amino esters by
hydroaminomethylation. Hydrocarboxylation and alkoxycarbonylation lead
to branched dicarboxylic acids or their
esters, respectively.
4.2 · Reactions at the C = C Double Bond of Unsaturated Oleochemicals