106-70-7Relevant articles and documents
Heterogeneous catalysis in an oscillatory baffled flow reactor
Eze, Valentine C.,Phan, Anh N.,Pirez, Cyril,Harvey, Adam P.,Lee, Adam F.,Wilson, Karen
, p. 2373 - 2379 (2013)
The first demonstration of heterogeneous catalysis within an oscillatory baffled flow reactor (OBR) is reported, exemplified by the solid acid catalysed esterification of organic acids, an important prototypical reaction for fine chemicals and biofuel synthesis. Suspension of a PrSO3H-SBA-15 catalyst powder is readily achieved within the OBR under an oscillatory flow, facilitating the continuous esterification of hexanoic acid. Excellent semi-quantitative agreement is obtained between OBR and conventional stirred batch reaction kinetics, demonstrating efficient mixing, and highlighting the potential of OBRs for continuous, heterogeneously catalysed liquid phase transformations. Kinetic analysis highlights acid chain length (i.e. steric factors) as a key predictor of activity. Continuous esterification offers improved ester yields compared with batch operation, due to the removal of water by-product from the catalyst, evidencing the versatility of the OBR for heterogeneous flow chemistry and potential role as a new clean catalytic technology. The Royal Society of Chemistry 2013.
Simple, rapid procedure for the synthesis of chloromethyl methyl ether and other chloro alkyl ethers
Berliner, Martin A.,Belecki, Katherine
, p. 9618 - 9621 (2005)
Zinc(II) salts catalyze the reaction between acetals and acid halides to provide haloalkyl ethers in near-quantitative yield. Reactions from millimole to mole scale are typically complete in 1-4 h with 0.01 mol % catalyst. The solutions of haloalkyl ethers thus obtained can be utilized directly in reactions in which the presence of the ester byproduct does not interfere. Excess haloalkyl ether is destroyed on workup, thereby minimizing exposure to this class of carcinogenic compounds.
The Co-promotion effect of Mo and Nd on the activity and stability of sulfated zirconia-based solid acids in esterification
Jiang, Kanghua,Tong, Dongmei,Tang, Jinqiang,Song, Ruili,Hu, Changwei
, p. 46 - 51 (2010)
SO42-/ZrO2-MoO3 (SZM), SO 42-/ZrO2-Nd2O3 (SZN) and SO42-/ZrO2-MoO3-Nd2O 3 (SZMN) solid acids catalysts were prepared and characterized by XRD, NH3-FTIR, NH3-TPD and TG-DTG. The activities and stabilities of the catalysts for the esterification of fatty acids were investigated. Experimental and characterization results show that the excellent activity and stability of SZMN are attributed to the firm combination of sulfur species with t-ZrO2. The co-addition of Mo and Nd increases the dispersion of t-ZrO2 and stabilizes the structure of small-crystallite t-ZrO2, which is favorable to increasing the acid sites amount, strengthening the acidity, and then enhancing the activity and stability of the catalyst.
Methylation of Aliphatic and Aromatic Carboxylic Acids with Dimethyl Carbonate under the Influence of Manganese and Iron Carbonyls
Khusnutdinov,Shchadneva,Mayakova, Yu. Yu.
, p. 15 - 19 (2018)
The synthesis of methyl esters has been carried out via the reaction of aliphatic and aromatic carboxylic acids with dimethyl carbonate in the presence of manganese and iron carbonyls. The optimal ratio of catalyst and reagents and other conditions for the synthesis of methyl esters of carboxylic acids with high yield have been found.
MOFs based on 1D structural sub-domains with Br?nsted acid and redox active sites as effective bi-functional catalysts
Díaz, Urbano,Moreno, José María,Velty, Alexandra
, p. 3572 - 3585 (2020)
A novel family of lamellar MOF-type materials, which contain Br?nsted acid sites together with redox active centers, based on assembled 1D organic-inorganic nanoribbons were obtained through direct solvothermal synthesis routes, using specific monotopic benzylcarboxylate spacers with thiol substituents in thepara-position like structural modulator compounds and effective post-synthesis oxidized treatments to generate accessible sulfonic groups. Low-dimensional aluminum metal-organic materials, containing free sulfonic pendant groups (Al-ITQ-SO3H), were successfully tested in several acid reactions, such as acetalization, esterification and ring opening of epoxides with a significant impact on fine chemistry processes. The direct introduction of stabilized Pd nanoparticles, cohabitating with pendant sulfonic groups, allowed the preparation of active bi-functional MOF-type hybrid materials (Al-ITQ-SO3H/Pd) capable of carrying out one-pot two-step oxidation-acetalization reactions, exhibiting high yield and high activity during consecutive catalytic cycles.
Acylated dolabellane-type diterpenes from Nigella sativa seeds with triglyceride metabolism-promoting activity in high glucose-pretreated HepG2 cells
Morikawa, Toshio,Ninomiya, Kiyofumi,Xu, Fengming,Okumura, Naomichi,Matsuda, Hisashi,Muraoka, Osamu,Hayakawa, Takao,Yoshikawa, Masayuki
, p. 198 - 204 (2013)
Two new acylated dolabellane-type diterpenes, nigellamines B3 (9) and D (10), were isolated from Nigella sativa (Ranunculaceae) seeds using column chromatography and preparative HPLC. Their structures were determined based on chemical and physi
A NOVEL OXO FATTY ACID IN PLANTAGO OVATA SEED OIL
Jamal, Sajid,Ahmad, Ishtiaque,Agarwal, Rajiv,Ahmad, Mashood,Osman, Sheikh Mohammad
, p. 3067 - 3069 (1987)
Key Word Index-Plantago ovata; Plantaginaceae; seed oil; 9-oxoocadec-cis-12-enoic acid. Plantago ovata seed oil contains two oxygenated fatty acids one of which is the known 9-hydroxyoctadec-cis-12-enoic acid.The other is 9-oxooctadec-cis-12-enoic acid a new acid.The structural elucidation of this novel compound is described.
Ultralow-Molecular-Weight Stimuli-Responsive and Multifunctional Supramolecular Gels Based on Monomers and Trimers of Hydrazides
Wu, Dehua,Song, Jintong,Qu, Lang,Zhou, Weilan,Wang, Lei,Zhou, Xiangge,Xiang, Haifeng
, p. 3370 - 3378 (2020)
The simpler, the better. A series of simple, neutral and ultralow-molecular-weight (MW: 140–200) hydrazide-derived supramolecular gelators have been designed and synthesized in two straightforward steps. For non-conjugated cyclohexane-derived hydrazides, their monomers can self-assemble to form gels through intermolecular hydrogen bonds and dipole-dipole interactions. Significantly, conjugated phthalhydrazide can self-aggregate into planar and circular trimers through intermolecular hydrogen bonds and then self-assemble to form gels through intermolecular π–π stacking interactions. It is interesting that these simple gelators exhibit unusual properties, such as self-healing, multi-response fluorescence, and visual and selective recognition of chiral (R)/(S)-1,1′-binaphthalene-2,2′-diamine and S2? through much different times of gel re-formation and blue-green color change, respectively. These results underline the importance of supramolecular gels and extend the scope of supramolecular gelators.
Optimized double kinetic resolution for the preparation of (S)-solketal
Vaenttinen, Eero,Kanerva, Liisa T.
, p. 923 - 933 (1997)
The lipase AK (lipase from Pseudomonas sp.)-catalysed alcoholysis of racemic solketal (2,2-dimethyl-1,3-dioxolane-4-methanol) esters and acylation of solketal in organic solvents proceeded with E = 20-25. This enabled the preparation of the more reactive (S)-enantiomer with more than 30% total isolated yield (based on the racemate) and 95% ee by a double kinetic resolution strategy consisting of enzymatic acylation-chemical saponification-enzymatic acylation or enzymatic alcoholysis-enzymatic acylation sequences. Numerical calculations and theoretical plots for the optimal termination conversions for the 1st and 2nd resolution steps as well as for the find yields as the function of E is considered.
Branched Selectivity in the Pd-Catalysed Methoxycarbonylation of 1-Alkenes
Arderne, Charmaine,Guzei, Llia A.,Holzapfel, Cedric W.,Bredenkamp, Tyler
, p. 1084 - 1093 (2016)
The methoxycarbonylation of alkenes by palladium(II) complexes with P,O-donor ligands [(2-methoxyphenyl)diphenylphosphine (L-2), bis(2-methoxyphenyl) phenyl phosphine (L-3) and tris(2-methoxyphenyl) phosphine (L-4)] has been investigated. The results show that the Pd complexes derived from these ligands provide high regioselectivity for the branched esters from 1-pentene and 1-hexene (>80 %). Various parameters (including temperature, pressure, acid concentration) were optimized to improve the performance of the catalyst system. Higher temperatures afforded higher regioselectivity; but effected rapid catalyst decomposition. Acceptable turnover frequencies, conversions as well as catalyst stability could be obtained at higher L/Pd ratios. The dramatic change in regioselectivity is rationalised on the basis of the hemi-lability of the o-methoxy moiety, which may lead to ligand dissociation from L2PdX2 (L=ligand, X=Cl) rather than the expected dissociation of X. In support of our hypothesis, direct evidence for the coordination of the o-methoxy to the Pd centre was demonstrated by the crystal structure. To the best of our knowledge, this work provides the first reported route to valuable branched esters through the methoxycarbonylation of alkenes at suitable rates.
