93-29-8Relevant articles and documents
One-pot hydroformylation/O-acylation of propenylbenzenes for the synthesis of polyfunctionalized fragrances
Delolo, Fábio G.,Vieira, Gabriel M.,Villarreal, Jesus A.A.,dos Santos, Eduardo N.,Gusevskaya, Elena V.
, p. 272 - 279 (2020/06/17)
A process involving the hydroformylation/O-acylation of propenylbenzenes with a phenolic group is described for eugenol, isoeugenol, chavicol, propenyl guaethol, 2-allylphenol, and 2-allyl-6-methylphenol. The reactions occur in parallel, under the same reaction conditions in anisole, a solvent with an impressive sustainability rank comparable to those of ethanol and water. The products contain formyl and acetoxy moieties, both established olfactory groups in flavor and fragrance industry, and present potential as new fragrance components with less allergenic properties. To the best of our knowledge, this is the first time that a one-pot process involving hydroformylation combined with further functionalization in a remote site is described.
Method for synthesizing vanillin from eugenol through ozone oxidation
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, (2020/12/31)
The invention relates to the technical field of organic chemical synthesis, in particular to a method for synthesizing vanillin from eugenol through ozone oxidation. The method comprises the followingsteps: adding dichlorotris(triphenylphosphine)ruthenium serving as a catalyst into eugenol to perform isomerization reaction to obtain isoeugenol, performing esterification reaction to obtain isoeugenol acetate, performing ozonation, and performing reducing; and carrying out alcoholysis and refining on the acetyl vanillin to obtain a pure product. The method solves the problems of low productionyield, use of a metal oxidant and difficult treatment of wastewater in the eugenol method in the prior art, eugenol isomerization adopts dichlorotris(triphenylphosphine)ruthenium as a catalyst, no wastewater is generated in the process, isoeugenol acetate is oxidized by ozone, the use of a heavy metal oxidant is avoided, and the method conforms to the green development trend. The method has the advantages of environmental protection and high yield.
Method for synthesizing E-methyl styrene compound
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Page/Page column 7, (2020/03/25)
The method for preparing E-pyridyl or alkyl-substituted,bipyridine, in a solvent, in the presence of nitrogen protection, in, reaction 0 °C -50 °C in the presence of a metal nickel salt 24 - 36h, ligand and an additive is E, and the preparation method disclosed by the invention has the advantages, cheap 2,2 ’ - raw materials, easiness in obtaining 2,2 ’ - and the like. The ligand is,bipyridine or an alkyl-substituted bipyridyl compound, in the. presence of a nitrogen, protection agent, in a solvent.
A Pd-Catalyzed Site-Controlled Isomerization of Terminal Olefins
Ren, Wenlong,Sun, Fei,Chu, Jianxiao,Shi, Yian
supporting information, p. 1868 - 1873 (2020/03/03)
An effective Pd-catalyzed isomerization of olefins with 2-PyPPh2 as the ligand is described. A wide variety of trans-2-olefins bearing various functional groups can be obtained with high regio- A nd stereoselectivity under mild reaction conditions. The ligand is crucial for the reaction.
Free Radical Scavenging Activity of Essential Oil of Eugenia caryophylata from Amboina Island and Derivatives of Eugenol
Julianus Sohilait, Hanoch,Kainama, Healthy
, p. 422 - 428 (2019/08/01)
Essential oil from Eugenia caryophylata was normally used to heal many different deseaces. Various chemical compositions of essential oil distilled and steamed of Moluccas Eugenia caryophylata has been investigated by many different researchers. Even though an intensive research has been carried out of the local chemotypes, a very detail study has not been fully investigated to find out the complete chemical compounds from the plant essential oil and its content associated with their biological activities. In present paper, we assess the free radical scavenging of E. caryophylata collected from Moluccas islands, Indonesia. Essential oil was extracted from leaves, buds, and stems of plant by steam distillation and analyzed using GC-FID and GC-MS. The result showed that free radical activity of essential oil, main constituent and its derivatives were analized using in vitro method. Essential oil activity from stem obtained as (0.82±0.15 μg/mL) was higher than that from bud and leaf possessing both 1,1-diphenyl-2-picrylhydrazyl (DPPH) and (2,2'-azino-bis-3-ethylbenzthizoline-6-sulphonic acid (ABTS) radical scavenging assays by sinergism of eugenol, eugenyl acetate, β-caryophylene and humulene. The activity of isoeugenol (2) (3.59±0.54 μM) and (5.0±0.53 μM) scavenging DPPH and ABTS, respectively, as derivatives eugenol was higher than (3), (4) and (5). Although (6) was active originally, it was inactive after conversion of the ester. While the change of the double bond of location to conjungation structure caused more activity scavenging radicals than the starting molecule.
Hydrophilic (ν6-Arene)-Ruthenium(II) Complexes with P-OH ligands as catalysts for the isomerization of allylbenzenes and C-H bond arylation reactions in water
González-Fernández, Rebeca,Crochet, Pascale,Cadierno, Victorio
, p. 3696 - 3706 (2019/10/11)
Half-sandwich ruthenium(II) complexes containing ν6-coordinated 3-phenylpropanol and phosphinous-acid-type ligands, namely, [RuCl2(ν6-C6H5CH2CH2CH2OH){P(OH)R2}] (R = Me (2a), Ph (2b), 4-C6H4CF3 (2c), 4-C6H4OMe (2d), OMe (2e), OEt (2f), and OPh (2g), have been synthesized in 44-88% yield by reacting [RuCl2{ν6:κ1(O)-C6H5CH2CH2CH2OH}] (1) with the appropriate pentavalent phosphorus oxide R2P(═O)H. The structure of [RuCl2(ν6-C6H5CH2CH2CH2OH){P(OH)Me2}] (2a) was unequivocally confirmed by X-ray diffraction methods. Compounds 2a-g proved to be catalytically active in the isomerization of allylbenzenes into the corresponding (1-propenyl)benzene derivatives employing water as the sole reaction solvent, with [RuCl2(ν6-C6H5CH2CH2CH2OH){P(OH)(OPh)2}] (2g) showing the best performance and a broad substrate scope (73-93% isolated yields with E/Z ratios around 90:10 employing 1 mol % of 2g and 3 mol % of K2CO3, and performing the catalytic reactions at 80 °C for 4-24 h). The results herein presented show for the first time the utility of phosphinous acids as auxiliary ligands for metal-catalyzed olefin isomerization processes, reactions in which a cooperative role for the P - OH unit is proposed. On the other hand, the utility of complexes 2a-g as catalysts for ortho-arylation reactions of 2-phenylpyridine in water is also briefly discussed.
From Syzygium aromaticum (clove) extracting Syzygium aromaticum (clove) phenol preparation of vanillin method (by machine translation)
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, (2017/10/10)
The present invention provides from Syzygium aromaticum (clove) extracting Syzygium aromaticum (clove) phenol preparation of vanillin method, comprises the following steps: (1) (1) Syzygium aromaticum (clove) phenol extraction and separation of: weighing Syzygium aromaticum (clove) flower drying bud, water vapor distillation, until clear distillate, non-oil bead to trickle out, stop heating, collecting distillate liquid, extraction, to obtain Syzygium aromaticum (clove) phenol; (2) the isomerization of Syzygium aromaticum (clove) phenol: to the rhodium is trichloride catalyst, through Syzygium aromaticum (clove) phenol of the isomerization reaction of preparing Syzygium aromaticum (clove) phenol; (3) phenol hydroxy protection: step (2) obtained in the different Syzygium aromaticum (clove) phenol and acetic anhydride reaction generating different Syzygium aromaticum (clove) acetate; (4) the oxidation reaction of olefinic: potassium permanganate in step (3) obtained in the different Syzygium aromaticum (clove) acetate oxidized into aldehyde group of the carbon-carbon double bond, preparation of vanillin acetate; (5) the preparation of vanillin. The method of the invention, using natural product as raw materials, is easy to obtain, resources are abundant, the production process is easy to control, easy separation of product, production cycle fast, there are extensive market application prospect. (by machine translation)
A novel synthesis of isoeugenol, [ring-(U)-14C]
Immoos, John E.
, p. 419 - 424 (2015/11/18)
A novel method for the preparation of isoeugenol, [ring-(U)-14C] is presented. Phenols and phenyl esters substituted in the para position with 1-hydroxyethyl or 1-hydroxypropyl acetate esters when treated with 1,8-diazabicyclo[5.4.0]undec-7-ene in dimethylformamide (DMF) eliminate the alkyl carboxylate function to give the unsaturated compound. The reaction fails with unsubstituted or ether substituted phenyl 1-hydroxyacetate esters.
Selective cleavage of the Cα-Cβ linkage in lignin model compounds via Baeyer-Villiger oxidation
Patil, Nikhil D.,Yao, Soledad G.,Meier, Mark S.,Mobley, Justin K.,Crocker, Mark
, p. 3243 - 3254 (2015/03/18)
Lignin is an amorphous aromatic polymer derived from plants and is a potential source of fuels and bulk chemicals. Herein, we present a survey of reagents for selective stepwise oxidation of lignin model compounds. Specifically, we have targeted the oxidative cleavage of Cα-Cβ bonds as a means to depolymerize lignin and obtain useful aromatic compounds. In this work, we prepared several lignin model compounds that possess structures, characteristic reactivity, and linkages closely related to the parent lignin polymer. We observed that selective oxidation of benzylic hydroxyl groups, followed by Baeyer-Villiger oxidation of the resulting ketones, successfully cleaves the Cα-Cβ linkage in these model compounds. This journal is
Modular palladium bipyrazoles for the isomerization of allylbenzenes - Mechanistic considerations and insights into catalyst design and activity, role of solvent, and additive effects
Spallek, Markus J.,Stockinger, Skrollan,Goddard, Richard,Trapp, Oliver
experimental part, p. 1466 - 1480 (2012/09/11)
The catalytic activity of novel bidentate N,N-chelated palladium complexes derived from electron excessive, backbone fused 3,3'-bipyrazoles in the selective isomerization of terminal arylpropenoids and 1-alkenes is described. The catalysts are easily modified by appropriate wing tip substitution, while maintaining the same bulky, rigid unreactive aliphatic backbone. Eleven novel palladium complexes with different electronic and steric properties were investigated. Their performance in the palladium(II)-catalyzed isomerization of a series of substituted allylbenzenes was evaluated in terms of electronic as well as steric effects. Besides the clear finding of a general trend towards higher catalyst activity with more electron-donating properties of the coordinated N,N-bidentate ligands, we found that the catalytic process strongly depends on the choice of solvents and additives. Extensive solvent screening revealed that reactions run best in a 2:1 toluene-methanol mixture, with the alcohol employed being a crucial factor in terms of electronic and steric factors. A reaction mechanism involving a hydride addition-elimination mechanism starting with a palladium hydride species generated in situ in alcoholic solutions, as corroborated by experiments using deuterium labeled allylbenzene, seems to be most likely. The proposed mechanism is also supported by the observed reaction rate orders of κobs[cat.]≈1 (0.94), κobs [substrate]=0.20→1.0 (t→∞) and κobs [methanol]=-0.51 for the isomerization of allylbenzene. Furthermore, the influence of acid and base, as well as the role of the halide coordinated to the catalyst, are discussed. The system catalyzes the isomerization of allylbenzenes very efficiently yielding high E:Z selectivities under very mild conditions (room temperature) and at low catalyst loadings of 1 mol% palladium even in unpurified solvents. The integrity and stability of the catalyst system were confirmed by multiple addition reaction cycles, successive filtration and isolation experiments, and the lack of palladium black formation. Copyright
