Methyl 10-undecenoate Research Articles

2-Phosphine-pyridine-N-oxide palladium and nickel catalysts for ethylene polymerization and copolymerization with polar monomers

A new family of [P,O] late transition metal catalysts, namely 2-phosphine-pyridine-N-oxide palladium complexes Pd1~Pd4 {[κ2(P,O)-2-Ar2P-6-R-(C5H3NO)]PdMeCl} (Pd1: Ar = Ph, R = H; Pd2: Ar = 2-MeO-C6H4, R = H; Pd3: Ar = Ph, R = tBu; Pd4: Ar = 2-MeO-C6H4, R = tBu) and nickel complexes Ni1~Ni4 {[κ2(P,O)-2-Ar2P-6-R-(C5H3NO)]Ni(allyl)}[BArF] (Ni1: Ar = Ph, R = H; Ni2: Ar = 2-MeO-C6H4, R = H; Ni3: Ar = Ph, R = tBu; Ni4: Ar = 2-MeO-C6H4, R = tBu) and Ni5 {[κ2(P,O)-2-Ph2P-6-tBu-(C5H3NO)]2Ni(allyl)}[BArF], was synthesized and comprehensively characterized by NMR spectroscopy, single-crystal X-ray diffraction, and elemental analysis. These new [P,O] palladium and nickel catalysts were evaluated for the (co)polymerization of ethylene. Among the synthesized catalysts, palladium catalysts Pd2 and Pd4 oligomerized ethylene with high activities of 106 g mol−1 h−1, while the nickel counterparts could polymerize ethylene in higher activities and higher polymer molecular weights, among which Ni4 preferred to afford polyethylene with the highest molecular weight. Moreover, Ni4 could catalyze the copolymerization of ethylene and biorenewable polar comonomer methyl 10-undecenoate, with the activity up to 105 g mol−1 h−1 and the incorporation of 0.4–1.2 mol%.

Selective Ruthenium‐Catalyzed Hydroaminomethylation of Unsaturated Oleochemicals

AbstractRhodium‐catalyzed hydroaminomethylation (HAM) is recently described as an innovative way to functionalize triglycerides. In the search to reduce production costs, rhodium is sought to be replaced by ruthenium whose price is currently more than 20 times lower. In this study, HAM of unsaturated oleochemicals using ruthenium precursors is proceeded under phosphine‐free conditions. The experimental conditions are optimized by changing the nature of the solvent, the reaction temperature, and the CO/H2 pressure. While rhodium leads to good catalytic activity and low chemoselectivity (mixture of hydroxyl and amino groups), ruthenium proves to be less active but more chemoselective as amino‐substituted products are mainly formed. Of interest, HAM of methyl 10‐undecenoate (MU) occurs in a highly chemo‐ and regioselective fashion using acetonitrile as solvent.Practical Applications: Selective Ru‐catalyzed hydroaminomethylation can be implemented on an industrial scale for the conversion of unsaturated oleochemicals into amines. This finding is of importance as the obtained amino‐products can be used in many industrial areas such as surfactants, polymers, or lubricants.

Sterics versus electronics: Imine/phosphine-oxide-based nickel catalysts for ethylene polymerization and copolymerization

A series of imine/phosphine-oxide ligands was synthesized and characterized. These ligands are easily prepared in a modular fashion, with positions that are independently tunable. The corresponding nickel allyl complexes were synthesized and serve as single-component catalysts for the homopolymerization of ethylene. It is generally believed that sterically bulky substituents lead to high polymer molecular weights during olefin polymerization. In this system, however, catalysts bearing the sterically bulky dibenzhydryl substituent afforded polyethylenes with much lower molecular weights than those bearing the sterically unhindered isopropyl substituent. Based on control experiments, theoretical calculations, and literature evidence, we propose that electronic effects override steric effects and play dominant roles in this nickel system. Efficient copolymerizations of ethylene with methyl 10-undecenoate and 6-chloro-1-hexene were also facilitated by this system without the need for any cocatalyst or protecting agent.

Position Makes the Difference: Electronic Effects in Nickel-Catalyzed Ethylene Polymerizations and Copolymerizations.

A series of phosphine-sulfonate ligands and the corresponding nickel complexes are prepared and characterized. These ligands are specifically designed to bear systematically varied electron-donating and -withdrawing substituents (H, OMe, NMe2, CF3, and Me). More importantly, these substituents are installed at different positions on the ligand framework, namely, the para-position of the phenylphosphino group (position X), and para to the arylsulfonate group of the main ligand (position Y). These nickel complexes are highly active single-component catalysts for the polymerization of ethylene. An electron-donating substituent at position X or an electron-withdrawing substituent at position Y is beneficial to the properties of these nickel catalysts. Specifically, the catalyst bearing the NMe2 substituent at position X exhibits high stability and high activity (3.3 × 106 g mol-1 h-1), and catalyzes the formation of polyethylene of high molecular weight ( Mn 405 000) and high melting point ( Tm 138.5 °C). This catalyst also mediates the efficient copolymerizations of ethylene with methyl 10-undecenoate, 6-chloro-1-hexene, and trimethoxyvinylsilane.

Experimental determination and association model for the solubilities of methyl 10-undecenoate with methyl ricinoleate in supercritical carbon dioxide

The mixture solubilities of methyl 10-undecenoate (M10U) + methyl ricinoleate (MR) in supercritical carbon dioxide (SCCO2) were determined at temperatures from 313 to 333 K, and pressures from 10 to 18 MPa. At constant pressure, the solubilities decreased with an increase with temperature for the investigated range of operating conditions. The maximum solubility enhancement for the current mixture was observed to be 32% for the MR in a mixture of M10U + MR. The maximum selectivity of SCCO2 was 12 towards M10U in a mixture of M10U + MR. The experimental data obtained was internally consistent, as verified by Mendez-Teja model. A new association theory based model was derived and used to model the solubilities of the investigated mixture in SCCO2 along with the literature data.

Experimental determination and development of solution theory based model for the mixture solubilities of 10-undecenoic acid with methyl 10-undecenoate and methyl ricinoleate in supercritical carbon dioxide

The solubilities of liquid mixtures of 10-undecenoic acid + methyl 10-undecenoate, and 10-undecenoic acid + methyl ricinoleate in SCCO2 were determined at T = 313–333 K and P = 10–18 MPa. The selectivity is higher towards methyl 10-undecenoate in a mixture of 10-undecenoic acid + methyl 10-undecenoate, whereas the selectivity is higher towards 10-undecenoic acid in a mixture of 10-undecenoic acid + methyl ricinoleate. A new model was developed based on the solution theory coupled with regular solution theory. The absolute average relative deviation (AARD%) obtained using the new model for the system of 10-undecenoic acid + methyl 10-undecenoate was 10.5 and 9.10 for the 10-undecenoic acid and methyl 10-undecenoate, respectively, whereas for the system of 10-undecenoic acid + methyl ricinoleate, the AARD% was 4.71 and 4.91 for the 10-undecenoic acid and methyl ricinoleate, respectively. These AARDs were significantly lower than the existing models indicating utility of the new model.

Imidazole end-functionalized polycyclooctenes from chain-transfer ring-opening metathesis polymerization and aminolysis reactions

Imidazole end-functionalized polycyclooctene derivatives were synthesized using a two-step procedure; combining ring-opening metathesis polymerization (ROMP)/cross-metathesis (CM) and aminolysis reaction. ROMP/CM of cyclooctene (COE) in the presence of methyl-10-undecenoate (MU) as a chain transfer agent in the presence of Grubbs first generation catalyst (G1) at 40 °C afforded mono ester end-functionalized (MF) as the major and bis ester end-functionalized (DF) polycyclooctene as the minor product. No isomerized mono ester end-functionalized (IMF) polycyclooctene was formed during G1 catalyzed ROMP/CM reactions. The post-polymerization modification of MF in the presence of 1-(3-aminopropyl) imidazole and different catalysts (Sn(Oct)2, Ti(OiPr)4 and triazabicyclodecene (TBD) in THF at 70 °C afforded imidazole end-functionalized polyolefins in excellent yields. All polymers were characterized by means of MALDI ToF-MS, 1H and 13C NMR spectrometry and Size Exclusion Chromatography (SEC) analyses. The solvent selectivity and catalyst screening experiments were carried out for both ROMP/CM and aminolysis reactions to determine the optimum reaction conditions.

Evaluation of new density based model to correlate the solubilities of ricinoleic acid, methyl ricinoleate and methyl 10-undecenoate in supercritical carbon dioxide

The solubilities of ricinoleic acid, methyl ricinoleate, and methyl 10-undecenoate were determined in supercritical carbon dioxide (SCCO2). The solubility measurements were performed in the range of temperatures of 313–333K, and pressures of 10–18MPa. The solubilities followed a trend of methyl 10-undecenoate>methyl ricinoleate>ricinoleic acid for the investigated compounds. A new model was derived using the solution theory and regular solution theory for the activity coefficient for correlating the solubility data. The solubility data were fitted using the new model and the average absolute relative deviation (AARD) for each compound was obtained. It was found to be 1.66%, 5.30%, and 6.43% for ricinoleic acid, methyl ricinoleate, and methyl 10-undecenoate, respectively. These AARD values are comparable to other three parameter solution theory model reported in literature indicating the utility of the developed model.

A Well-Defined Ni(II) α-Diimine Catalyst Supported on Sulfated Zirconia for Polymerization Catalysis

The reaction of (α-diimine)NiMe2 (α-diimine = (2,6-iPr2-C6H3)N═CMeMeC═N(2,6-iPr2-C6H3)) with partially dehydroxylated sulfated zirconia (SZO300) in MeCN results in the formation of [(α-diimine)NiMe(NCMe)][SZO300] ([1][SZO300]) and methane. Reactions in Et2O resulted in mixtures of [(α-diimine)NiMe(OEt2)][SZO300] ([2][SZO300]) and [(α-diimine)NiMe(OEt2)][MeSZO300] ([2][MeSZO300]), which were characterized by solid-state NMR spectroscopy. Contacting these solids with ethylene and monitoring the reaction by solid-state NMR showed that Ni–Me sites insert ethylene. [1][SZO300] and [2][SZO300]/[2][MeSZO300] are active ethylene polymerization catalysts and show properties similar to those of closely related homogeneous catalysts. [2][SZO300]/[2][MeSZO300] copolymerizes ethylene and methyl 10-undecenoate to form copolymers with up to 0.4% incorporation of the polar monomer.

Catalytic Oxyfunctionalization of Methyl 10-undecenoate for the Synthesis of Step-Growth Polymers

An efficient synthesis strategy for the preparation of two renewable polyesters and one renewable polyamide via catalytic oxyfunctionalization of methyl 10-undecenoate, a castor oil derived platform chemical, is described. The keto-fatty acid methyl ester (keto-FAME) is synthesized applying a cocatalyst-free Wacker oxidation process using a high-pressure reactor system. For this purpose, catalytic amounts of palladium chloride are used in the presence of a dimethylacetamide/water mixture and molecular oxygen as sole reoxidant. The thus derived AB monomers (hydroxy-esters, amine-ester) are synthesized from the obtained keto-FAME through Baeyer–Villiger oxidation and subsequent transesterification, reduction, or reductive amination, respectively. The resulting AB step-growth monomers are then studied in homopolymerizations using 1,5,7-triazabicyclo[4.4.0]dec-5-ene, DBU, and titanium(IV) isopropoxide as transesterification catalyst, yielding polymers with molecular weights (Mn) up to 15 kDa. The polyesters and the polyamide are carefully characterized by FTIR, SEC, 1H-NMR spectroscopy, and differential scanning calorimetry analysis.

Enhancing Thermal Stability and Living Fashion in α-Diimine–Nickel-Catalyzed (Co)polymerization of Ethylene and Polar Monomer by Increasing the Steric Bulk of Ligand Backbone

Development of thermally stable nickel-based catalysts is highly desirable for industrial gas-phase olefin polymerizations. On the basis of the strategy of promoting the thermostability of nickel catalyst by the ligand backbone, we herein reported novel dibenzobarrelene-derived α-diimine nickel precatalysts for ethylene polymerization. Increasing the steric bulk on the ligand backbone was expected to inhibit the N-aryl rotation of the α-diimine ligands by the repulsive interactions, thus enhancing thermal stability (100 °C) and living fashion a temperatures up to 80 °C. Bulk ligand backbone also improved tolerance of nickel catalyst toward polar groups, and the α-diimine nickel catalyst containing a 2,6-tBu-dibenzobarrelene backbone catalyzed living copolymerization of ethylene and methyl 10-undecenoate.

9,9-Dimethylxanthene-based binuclear phenoxy-imine neutral nickel(II) catalysts for ethylene homo- and copolymerization

Mononuclear neutral nickel catalyst Ni1 and binuclear complexes Ni2 and Ni3 based on rigid 9,9-dimethylxanthene frameworks featuring short Ni−Ni distances were synthesized, characterized and applied in ethylene (co)polymerization. Binuclear catalyst Ni2 exhibited higher activity in ethylene polymerization than corresponding mononuclear Ni1, and produce higher molecular weight polymer with a bimodal molecular weight distribution. Catalyst Ni2 is remarkably thermally robust, and still displaying promising activity at 93 °C. The polymer microstructure produced by Ni1 reveals a hyperbranched structure with a variety of branch types, while Ni2 product features methyl branches primarily. In the presence of comonomer 1,5-hexadiene, 1,7-octadiene, and methyl 10-undecenoate, mononuclear Ni1 suffers from either low catalytic activity or poor incorporation efficiency, while binuclear catalyst Ni2 effectively enchained these comonomers into the polymer chain, giving copolymer with unique microstructures.

Synthesis and evaluation of anti-oxidant and cytotoxic activities of novel 10-undecenoic acid methyl ester based lipoconjugates of phenolic acids.

The synthesis of five novel methyl 10-undecenoate-based lipoconjugates of phenolic acids from undecenoic acid was carried out. Undecenoic acid was methylated to methyl 10-undecenoate which was subjected to a thiol–ene reaction with cysteamine hydrochloride. Further amidation of the amine was carried out with different phenolic acids such as caffeic, ferulic, sinapic, coumaric and cinnamic acid. All synthesized compounds were fully characterized and their structures were confirmed by spectral data. The anti-oxidant activity of the synthesized lipoconjugates of phenolic acids was studied by the 2,2-diphenyl-1-picrylhydrazyl (DPPH) radical scavenging assay and also by the inhibition of linoleic acid oxidation in micellar medium by differential scanning calorimetry (DSC). The prepared compounds were also screened for their cytotoxic activity against five cell lines. It was observed that the lipoconjugates of caffeic acid, sinapic acid, ferulic acid, and coumaric acid displayed anticancer and anti-oxidant properties. The anticancer properties of these derivatives have been assessed by their IC50 inhibitory values in the proliferation of MDA-MB231, SKOV3, MCF7, DU 145 and HepG2 cancer cell lines.

Semi-Crystalline Polar Polyethylene: Ester-Functionalized Linear Polyolefins Enabled by a Functional-Group-Tolerant, Cationic Nickel Catalyst.

A dibenzobarrelene-bridged, α-diimine Ni(II) catalyst (rac-3) was synthesized and shown to have exceptional behavior for the polymerization of ethylene. The catalyst afforded high molecular weight polyethylenes with narrow dispersities and degrees of branching much lower than those made by related α-diimine nickel catalysts. Catalyst rac-3 demonstrated living behavior at room temperature, produced linear polyethylene (Tm =135 °C) at -20 °C, and, most importantly, was able to copolymerize ethylene with the biorenewable polar monomer methyl 10-undecenoate to yield highly linear ester-functionalized polyethylene.

Overcoming Phase-Transfer Limitations in the Conversion of Lipophilic Oleo Compounds in Aqueous Media-A Thermomorphic Approach.

A new process concept has been developed for recycling transition-metal catalysts in the synthesis of moderately polar products via aqueous thermomorphic multicomponent solvent systems. This work focuses on the use of "green" solvents (1-butanol and water) in the hydroformylation of the bio-based substrate methyl 10-undecenoate. Following the successful development of a biphasic reaction system on the laboratory scale, the reaction was transferred to a continuously operated miniplant to demonstrate the robustness of this innovative recycling concept for homogenous catalysts.

Soft amphiphilic polyesters obtained from PEGs and silicon fatty compounds: structural characterizations and self-assembly studies

Transesterification polymerizations between a silicon fatty ester derived from methyl 10-undecenoate and polyethylene glycol (PEG) monomers generate amphiphilic biopolyesters ​showing abilities to form micelle and fiber structures.

Hydroesterification of methyl 10-undecenoate in thermomorphic multicomponent solvent systems—Process development for the synthesis of sustainable polymer precursors

In this paper, we present a process concept for the atom economic hydroesterification of renewable methyl 10-undecenoate in thermomorphic multicomponent solvent (TMS) systems. Resulting dimethyl dodecanedioate is a polymer building block used e.g. in Nylon 6,12. As a suitable recycling technique a thermomorphic multicomponent solvent system consisting of methanol and dodecane is employed to recycle the palladium/1,2-bis(di-tert-butylphosphino)methyl)benzene/methanesulfonic acid catalyst. Product yields up to 79% and a high regioselectivtiy of 94% to the linear product are obtained. Low leaching of the catalyst into the product phase with 1% in respect of palladium and phosphorous is observed. Robustness and stability of the catalyst is shown in eight recycling runs without any loss of selectivity in the reaction.

One-pot ozonolytic synthesis of acyclic α,ω-bifunctional compounds from methyl 10-undecenoate and 10-undecen-1-ol

Transformations of peroxy products formed by ozonolysis of undecylenic acid derivatives (methyl ester and hydride reduction product, 10-undecen-1-ol) in various protic and aprotic solvents (MeOH, PriOH, tetrahydrofuran, 1: 5 AcOH–CH2Cl2 mixture), occurring under the action of such reductants as hydroxylamine and semicarbazide hydrochlorides, were studied. These reductants exhibit high performance and in some cases high chemoselectivity, which allowed the development of a number of one-pot procedures for the synthesis of acyclic α,ω-bifunctional compounds, the majority of which are widely used in medicine, perfumery, cosmetics, engineering, and chemical industry, e.g., as block synthons in targeted organic synthesis.

Olefin metathesis transformations in thermomorphic multicomponent solvent systems

Homogeneous catalysis is a major actor of modern chemistry with a growing impact on clean and sustainable chemical processes. However, for many industrial applications of homogeneously catalyzed reactions, an easy separation and recovery of the catalyst should be guaranteed. Temperature-dependent multicomponent solvent (TMS) systems have been evaluated in ruthenium catalyzed olefin metathesis transformations. Propylene carbonate was found a suitable solvent for the ruthenium catalyzed ring-closing and cross-metathesis transformations of a variety of substrates including renewable fatty esters. The potential of a TMS system consisting of propylene carbonate/ethyl acetate/cyclohexane was then evaluated in the cross-metathesis of the renewable methyl 10-undecenoate with methyl acrylate and acrylonitrile.

Ruthenium cyclopentadienylidene phosphorane complexes – Synthesis, characterization and catalysis

The synthesis of ruthenium complexes of cyclopentadienylidene phosphorane ligands C5H3R1–PR22R3 (a: R1 = H, R2 = R3 = Ph; b: R1 = tBu, R2 = Ph, R3 = Me; c: R1 = H, R2 = R3 = nBu; d: R1 = H, R2 = Ph; R3 = NHDip with Dip = 2,6-diisopropylphenyl) is described. The influence of steric and electronic effects of these ligands on spectroscopic and structural properties is analyzed by means of NMR spectroscopy and x-ray crystallography. Complexes of the form [Ru(η5-C5H3R1–PR22R3)(NCMe)3] [PF6]23a–c are examined concerning their activity in a representative alkene-alkyne coupling reaction. The influence of the sterically demanding phosphonium ionic tag at the Cp-moiety on the yield and regioselectivity of the coupling of methyl 10-undecenoate with 1-octyne is investigated.