- At Long Last: Olefin Metathesis Macrocyclization at High Concentration
-
Macrocyclic lactones, ketones, and ethers can be obtained in the High-Concentration Ring-Closing Metathesis (HC-RCM) reaction in high yield and selectivity at concentrations 40 to 380 times higher than those typically used by organic chemists for similar macrocyclizations. The new method consists of using tailored ruthenium catalysts together with applying vacuum to distill off the macrocyclic product as it is formed by the metathetical backbiting of oligomers. Unlike classical RCM, no large quantities of organic solvents are used, but rather inexpensive nonvolatile diluents, such as natural or synthetic paraffin oils. Moreover, use of a protecting atmosphere or a glovebox is not needed, as the new catalysts are perfectly moisture and air stable. In addition, some other cyclic compounds previously reported as unobtainable by RCM in neat conditions, or in high dilutions even, can be formed with the help of the HC-RCM method.
- Sytniczuk, Adrian,Dabrowski, Micha?,Banach, ?ukasz,Urban, Mateusz,Czarnocka-?niada?a, Sylwia,Milewski, Mariusz,Kajetanowicz, Anna,Grela, Karol
-
supporting information
p. 8895 - 8901
(2018/07/05)
-
- METHOD OF CYCLIC COMPOUNDS PRODUCTION IN OLEFINE METATHESIS REACTION AND USE OF RUTHENIUM CATALYSTS IN PRODUCTION OF CYCLIC OLEFINS IN OLEFINE METATHESIS REACTION
-
The invention relates to a method for the preparation of cyclic compounds in the metathesis of olefins from acyclic dienes comprising terminal and/or non-terminal C=C double bonds; the invention also relates to the use of homogeneous ruthenium complexes and homogeneous ruthenium complexes deposited on a solid support as catalysts and/or pre-catalysts for the preparation of cyclic olefins in olefin metathesis reactions. Formula (I)
- -
-
Page/Page column 38
(2018/11/22)
-
- Preparation of Musk-Smelling Macrocyclic Lactones from Biomass: Looking for the Optimal Substrate Combination
-
Macrocyclic musk belongs to a well-known and valued class of the fragrance family. Originally, natural musks were obtained from rectal musk glands which often led to the death of the animals. Recently, a lot of effort was invested to obtain such macrocycles in a synthetic way. This research presents a study on the preparation of macrocyclic lactones with the musk scent by ring-closing metathesis (RCM) using biomass-derived starting materials: oleic and 9-decenoic acid. An experimental rule correlating the C–C double bond substitution pattern in the starting diene and the yield for the RCM macrocyclization was proposed.
- Sytniczuk, Adrian,Leszczyńska, Agnieszka,Kajetanowicz, Anna,Grela, Karol
-
p. 3157 - 3166
(2018/09/14)
-
- Solvent- and base-free synthesis of wax esters from fatty acid methyl esters by consecutive one-pot, two-step catalysis
-
The one-pot, two-step synthesis of wax esters was successfully conducted by consecutive homogeneous ruthenium-catalysed hydrogenation-dehydrogenation reactions of fatty acid methyl esters, in the absence of solvent and of base additive. Under optimized conditions, excellent conversion and selectivity were reached. Furthermore, physicochemical investigations revealed that the resulting compounds display properties similar to benchmark commercial products extracted from natural sources of lesser availability compared to the herein considered bioresources, making this chemical route very promising regarding further potential industrial implementation.
- Nguyen,Raffa,Morin,Desset,Capet,Nardello-Rataj,Dumeignil,Gauvin
-
supporting information
p. 5665 - 5673
(2017/12/06)
-
- Guanidine based task specific ionic liquids for the synthesis of biolubricant range esters under solvent-free condition
-
Guanidine-based task specific ionic liquids (ILs) were synthesized from the reaction of 1,1,3,3-tetramethyl guanidine with protic acids and used for the synthesis of higher alcohol esters of fatty acids as biolubes under solvent free condition. The synthesized 1,1,3,3-tetramethylguanidinium hydrogen sulphate (TMG·HSO4) was found to be most effective among the different ILs including 1,1,3,3-tetramethylguanidinium acetate (TMG·Ac), 1,1,3,3-tetramethylguanidinium hydrogen phosphate (TMG·H2PO4) and 1,1,3,3-tetramethylguanidinium trifluoro acetate (TMG·TFA). The effect of various reaction parameters such as reaction temperature, reaction time, catalyst amount etc. has been studied. After completion the reaction the esterification product was isolated and the recovered IL was reused for several runs without loss in catalytic activity.
- Porwal, Jyoti,Kumar, Subodh,Kaul, Savita,Jain, Suman L.
-
p. 93640 - 93644
(2016/10/18)
-
- Method For Synthesising Esters
-
A method for synthesising a second ester from a first ester, the method including the following steps: a) placing a first ester and a catalyst in the presence of dihydrogen such as to obtain a first alcohol and a second alcohol; b) extracting the second alcohol from the reaction medium; c) reacting the first alcohol with the catalyst of step a) in order to obtain a second ester and dihydrogen; and d) recirculating the dihydrogen obtained in step c) by injecting same into step a).
- -
-
Paragraph 0085; 0087
(2016/10/27)
-
- Zirconium-containing metal organic frameworks as solid acid catalysts for the esterification of free fatty acids: Synthesis of biodiesel and other compounds of interest
-
Zr-containing metal organic frameworks (MOFs) formed by terephthalate (UiO-66) and 2-aminoterephthalate ligands (UiO-66-NH2) are active and stable catalysts for the acid catalyzed esterification of various saturated and unsaturated fatty acids with MeOH and EtOH, with activities comparable (in some cases superior) to other solid acid catalysts previously reported in literature. Besides the formation of the corresponding fatty acid alkyl esters as biodiesel compounds (FAMEs and FAEEs), esterification of biomass-derived fatty acids with other alcohols catalyzed by the Zr-MOFs allows preparing other compounds of interest, such as oleyl oleate or isopropyl palmitate, with good yields under mild conditions.
- Cirujano,Corma,Llabrés I Xamena
-
p. 213 - 220
(2015/02/19)
-
- Enzymatic esterification of fatty acid esters by tetraethylammonium amino acid ionic liquids-coated Candida rugosa lipase
-
Enzymatic production of fatty acid esters from the esterification of oleyl alcohol with various fatty acids was investigated by using two new tetraethylammonium amino acid ionic liquids-coated Candida rugosa lipase (ILs-CRL) as biocatalysts in hexane. Both enzyme derivatives were prepared by mixing Candida rugosa lipase with tetraethylammonium l-histidinate (IL1) and tetraethylammonium l-asparaginate (IL2). The ILs-CRL system containing the equivalent protein concentration as in CRL showed higher esterification activity especially on medium chain fatty acids (C12-C16) as compared to non-coated CRL. Hydrophilicity of ILs may play an important role in hydrogen bonding with enzyme surface and consequently stabilize the ILs-CRL.
- Abdul Rahman, Mohd Basyaruddin,Jumbri, Khairulazhar,Mohd Ali Hanafiah, Nurul Ain,Abdulmalek, Emilia,Tejo, Bimo Ario,Basri, Mahiran,Salleh, Abu Bakar
-
experimental part
p. 61 - 65
(2012/07/13)
-
- Engkabang fat esters for cosmeceutical formulation
-
Engkabang fat esters were synthesized from engkabang fat using an enzyme as catalyst. The main composition of the fat esters were oleyl palmitate, oleyl stearate and oleyl oleate. The percentage yield was 93.67%. Ternary phase diagrams systems containing fat esters/surfactant/water were constructed. Several regions appeared in the ternary phase diagrams such as isotropic, homogenous, liquid crystal, two-phase and three-phase regions. Increasing the hydrophilic-lipophilic balance value of the used surfactants gave a larger homogenous and isotropic region in ternary phase diagrams of engkabang fat esters/nonionic surfactant/deionized water. Isotropic and homogenous regions in the ternary phase diagram of engkabang fat esters: PEG-40 hydrogenated castor oil (2:1)/polyoxyethylene(20) sorbitan tri-oleate/deionized water, was the largest when compared to the other ternary phase diagrams. The isotropic and homogenous region can be used as a medium in formulation of cosmetics and pharmaceutical products such as creams, lotions, balms and lipsticks. AOCS 2010.
- Gani, Siti Salwa Abd,Basri, Mahiran,Rahman, Mohd Basyaruddin Abdul,Kassim, Anuar,Rahman, Raja Noor Zaliha Raja Abd,Salleh, Abu Bakar,Ismail, Zahariah
-
experimental part
p. 227 - 233
(2012/05/05)
-
- Melting points and viscosities of fatty acid esters that are potential targets for engineered oilseed
-
Our previous isolation of branched-chain fatty acid (BCFA) methyl esters from lanolin was improved and scaled up. Also, oleate esters of isopropanol, oleyl alcohol and normal alcohols of 1-12 carbons chain lengths were prepared. Esters were made by interesterification with sodium alcoholates and by esterification with Candida antarctica lipase. It proved easier to obtain pure esters by the enzymatic synthesis. Melting points and viscosities over the range of 0-70 °C were determined in order to better identify potential lubricant targets that might be produced by genetically modified oilseed crops. Isopropyl and butyl oleate have melting points of -33 and -32 °C, respectively and viscosities that range from ~17 cp (0 °C) to ~2.5 cp (70 °C). They should have suitable stability for lubricants. BCFA esters had viscosities similar to their straight chain analogs. Viscosities increased with alcohol chain length and decreased with temperature. The dependence of viscosity on temperature was fit with an equation based on Erying's rate equation. Some esters with branched acid or branched alcohol moieties, and some oleate esters might be utilized as biolubricants or biofuels on the basis of their melting points and viscosities.
- Yao, Linxing,Hammond, Earl,Wang, Tong
-
-
- Liquid-liquid biphasic synthesis of long chain wax esters using the Lewis acidic ionic liquid choline chloride·2ZnCl2
-
The first liquid-liquid biphasic synthesis of wax esters in a Lewis acidic ionic liquid, choline chloride·2ZnCl2 by the esterification of long chain carboxylic acids with long chain alcohols is described. The reported reaction system has the advantages of both homogeneous and heterogeneous catalysis with high product yield and the ease of product as well as catalyst separation without the use of an organic solvent. The ionic liquid studied plays the dual role of solvent as well as catalyst and is recycled up to six times without any significant loss of activity.
- Sunitha, Sadula,Kanjilal, Sanjit,Reddy, P. Srinivasa,Prasad, Rachapudi B.N.
-
p. 6962 - 6965
(2008/02/13)
-
- Hydrogenation of fatty esters over ruthenium-tin catalysts; characterization and identification of active centers
-
The selective hydrogenation of methyl oleate into oleyl alcohol was performed over RuSn/alumina catalysts. A maximum yield of unsaturated alcohol was obtained for a bulk atomic ratio to Sn/Ru = 4. The side reaction of the transesterification between methyl oleate and oleyl alcohol leading to oleyl oleate was strongly decreased. The ruthenium-tin catalysts prereduced with NaBH4 have been characterized by TPR and XPS analysis. The addition of tin increased the content of Ru° on the catalyst surface without modification of the total Ru content. When the catalysts were reduced with NaBH4, a decrease of the tin and ruthenium contents on the surface was observed. On the catalyst surface were found two separate tin oxide species which differed in the oxidation state of tin. The proportion and the repartition of each species was a function of the total tin content. Over such catalysts, the reaction scheme involved three steps: (1) the hydrogenation of the methyl oleate into the oleyl alcohol, (2) the transesterification reaction between the methyl oleate and the oleyl alcohol with the formation of the heavy oleyl oleate ester, (3) the hydrogenation of this heavy ester into oleyl alcohol. The first and the third steps could involve mixed ruthenium-tin sites while the second step could require tin species without an interaction with ruthenium. If it is assumed that the rate determining step is the oleyl oleate hydrogenation, the results of this study show that active centers corresponding to a stoechiometry Ru/SnOx = 2 could be involved in this reaction. The activation of esters (methyl oleate and oleyl oleate) would occur via a hemiacetal intermediate over these mixed sites where the more reduced tin species could be close to the ruthenium.
- Pouilloux,Autin,Guimon,Barrault
-
p. 215 - 224
(2007/10/03)
-
- Selective hydrogenation of methyl oleate into oleyl alcohol in the presence of ruthenium-tin-supported catalysts
-
The hydrogenation of methyl oleate (methyl 9Z-octadecenoate) into oleyl alcohol (9Z-octadecen-1-ol) is carried out in an autoclave at 8.0 MPa and 543 K with Ru-Sn catalysts.The activity and the selectivity of this catalytic system are linked to the preparation method, the nature of the support (alumina, silica, active carbon and zinc oxide) and to the tin content.Selectivities of 50 and 55 percent to unsaturated alcohol respectively were obtained with a Ru-Sn-B/alumina catalyst resulting from the co-reduction of metallic salts by sodium borohydride and a Ru-Sn/alumina catalyst prepared by a sol-gel method.Our work also showed that a previously unreported transesterification reaction between methyl oleate and oleyl alcohol occured rapidly and led to a 'higher' ester (oleyl oleate).This side-reaction significantly decreases the selectivity to unsaturated alcohol.Nevertheless, at higher conversion the oleyl oleate is gradually hydrogenated into oleyl alcohol. - Keywords: ruthenium; tin; boron; methyl oleate hydrogenation; oleyl alcohol; transesterification
- Piccirilli, Antoine,Pouilloux, Yannick,Pronier, Stephane,Barrault, Joel
-
p. 1109 - 1118
(2007/10/03)
-
- Synthesis of (2,3-13C2) eruric acid
-
The synthesis of (2,3-13C2) erucic acid, for use in metabolic studies, is reported. The synthesis employs a repeated 3 step reaction sequence using 13C labeled triethylphosphonoacetate to extend C(18:1), oleyl alcohol, by 4 carbons. The starting alcohol is first oxidized with PCC and the resulting aldehyde is condensed with triethyl(1-13C)phosphonoacetate. The product, an α,β unsaturated ester, is reduced with (Ph3PCuH)6 to ethyl eicosenoate. Reduction with LAH gives eicosenoyl alcohol. A repetition of the reaction sequence using triethyl(2-13C) phosphonoacetate results in ethyl(2,3-13C2)erucate. The (2,3-13C2) erucic acid, obtianed by hydrolysis with alcoholic KOH, gave 13C NMR signals of δ 24.6 and 34.1 ppm for C-3 and C-2 respectively with a J = 34.9 Hz. The overall yield was 5.5%.
- Olsen,Bukata
-
p. 899 - 906
(2007/10/02)
-
- Synthesis of Fatty Acid Ester by Corynebacterium sp. S-401
-
Resting cells and acetone-dried cells of Corynebacterium sp.S-401 catalyzed the fatty acid ester synthesis of various alcohols and fatty acids.These reactions were carried out in phosphate buffer and/or organic solvents.In some cases synthetic reactions of esters in nonpolar solvents, such as n-hexane and benzene, gave better results compared with those obtained in phosphate buffer.
- Seo, Chull Won,Yamada, Yasuhiro,Okada, Hirosuke
-
p. 405 - 410
(2007/10/02)
-
