Cross-metathesis Of Methyl Oleate Research Articles

A tunable family of CAAC-ruthenium olefin metathesis catalysts modularly derived from a large-scale produced ibuprofen intermediate.

A series of tunable CAAC-based ruthenium benzylidene complexes with increased lipophilicity derived from a ketone being a large-scale produced key substrate for a popular nonsteroidal anti-inflammatory drug-ibuprofen was obtained and tested in various olefin metathesis transformations. As a group, these catalysts exhibited higher activity than their known analogues containing a smaller and less lipophilic phenyl substituent on the α-carbon atom, but in individual reactions, the size of the N-aryl moiety was revealed as a decisive factor. For example, in the cross-metathesis of methyl oleate with ethylene (ethenolysis)-a reaction with growing industrial potential-the best results were obtained when the N-aryl contained an isopropyl or tert-butyl substituent in the ortho position. At the same time, in the RCM, CM, and self-CM transformations involving larger olefinic substrates, the catalysts with smaller aryl-bearing CAAC ligands, where methyl and ethyl groups occupy ortho, ortho' positions performed better. This offers a great deal of tunability and allows for selection of the best catalyst for a given reaction while keeping the general structure (and manufacturing method) of the ibuprofen-intermediate derived CAAC ligand the same.

PLANT OIL VALORIZATION BY CROSS-METATHESIS REACTIONS: SYNTHESIS OF FINE CHEMICALS FROM METHYL OLEATE

This work studies the production of high-value compounds by the cross-metathesis of methyl oleate (MO) with ethylene, cinnamonitrile and cinnamaldehyde using the 2nd generation Hoveyda-Grubbs complex (HG) as catalyst, either dissolved in toluene or supported on silica. Reactions were carried out in batch reactors between 313 and 343 K. The yield to cross-metathesis products (YC-M) for the MO cross-metathesis with cinnamonitrile and cinnamaldehyde increased with the initial molar reactant ratio (RCN/MO, RCA/MO), reaching YC-M values of 82% and 95%, respectively, at R = 7. No catalyst deactivation took place during the 400-min catalytic runs. The liquid-phase cross-metathesis of MO with ethylene (ethenolysis) was performed over HG(10%)/SiO2 catalysts, producing 1-decene and methyl 9-decenoate, a valuable intermediate for the synthesis of pheromones. At RC2/MO = 2.5, the selectivity to ethenolysis products was 77% at 82% MO conversion. The MO self-metathesis was the only side reaction observed in all the catalytic tests.

Cross metathesis of methyl oleate (MO) with terminal, internal olefins by ruthenium catalysts: factors affecting the efficient MO conversion and the selectivity

Cross metathesis (CM) of methyl oleate (MO) with cis-4-octene, cis-stilbene, allyltrimethylsilane by RuCl2(PCy3)(IMesH2)(CHPh) yielded CM products with high MO conversion, high selectivity; the effect of olefin substituents, conditions was explored.

Metathesis of renewable raw materials—influence of ligands in the indenylidene type catalysts on self-metathesis of methyl oleate and cross-metathesis of methyl oleate with (Z)-2-butene-1,4-diol diacetate

The influence of different N-heterocyclic carbene (NHC) and other neutral ligands on the outcome of the cross-metathesis reaction of methyl oleate with (Z)-2-butene-1,4-diol diacetate and self-metathesis of methyl oleate was studied for a series of indenylidene type Ru catalysts.

Metathesis of Unsaturated Fatty Acid Esters with a Reusable Ruthenium Catalyst

Metathesis of unsaturated fatty acid esters with a magnetic nanoparticle-supported Hoveyda-Grubbs catalyst 1 was described. Thus, self-metathesis of methyl oleate (2) was ­carried out in the presence of the immobilized Grubbs II catalyst 1 grafted onto magnetic nanoparticles (100 nm, matrix with starch) [2/1 (mol/mol) = 2008] to give dimethyl-9-octadecene-1,18-dioate (3) in 73% yield with 489 h-¹ TOF. Cross-metathesis of methyl oleate (2) and methyl acrylate (5) with 1 [2/1 (mol/mol) = 497] gave dimethyl undec-2-en-1,11-dioate (6) in 60% yield with 12 h-¹ TOF. Self-metathesis of a macro-monomer 8 using 1 [8/1 (mol/mol) = 98] ­afforded a polymer 9 in 90% yield with 29 h-¹ TOF.

Renewable Monomer Feedstocks via Olefin Metathesis: Fundamental Mechanistic Studies of Methyl Oleate Ethenolysis with the First-Generation Grubbs Catalyst

The conversion of seed oil based feedstocks such as methyl oleate into useful commercial raw materials via olefin metathesis has been a research focus for decades, due to their low cost and renewable supply, but technical success has been limited due to poor catalyst activities and turnovers. We report here recent studies on the cross-metathesis of methyl oleate with ethylene (ethenolysis) catalyzed by bis(tricyclohexylphosphine)benzylideneruthenium dichloride (1). At 25 °C/60 psig of ethylene, catalysis by 1 results in the highly selective formation of 1-decene and methyl 9-decenoate. However, reactivity losses limit the catalyst turnovers well below commercial viability in batch reactor operation. In an attempt to address the limitations of this chemistry, a combination of an experimental evaluation of the impact of process parameters, a detailed analysis of the fundamental reaction steps, kinetic modeling, and molecular modeling has been applied to develop a more detailed understanding of this complex catalytic pathway. These fundamental studies have led to a more complete understanding of the factors impacting catalyst performance and the identification of approaches necessary to achieve an economically viable process.

Olefin Metathesis. IV.

The metathesis of methyl oleate with the WCl6-cocatalyst system was investigated. Tetra-n-butyl-stannane, tetraethylstannane and triethylaluminum were effective as cocatalysts. The optimum reaction condition was considerably different from that for the metathesis of internal alkene having no functional group. The addition of methyl oleate or methyl stearate depressed the various side reactions in the metathesis of alkenes having no functional group. These facts indicate that in spite of the high reaction temperature, the relatively high selectivity is obtained in the metathesis of methyl oleate owing to the existence of its ester group. Cross metathesis of methyl oleate and 1-decene was examined.