cas 93-03-8, 3,4-Dimethoxybenzyl alcohol | Articles data

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Lundquist,Kirk
p. 1676
(1978)
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Zasosov et al.
(1971)
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Synthesis of (±)-3,4-dimethoxybenzyl-4-methyloctanoate as a novel internal standard for capsinoid determination by HPLC-ESI-MS/MS(QTOF)
Capsinoids exhibit health-promoting properties and are therefore compounds of interest for medical and food sciences. They are minor compounds present in relatively high concentrations in only a few number of pepper cultivars. It is desirable to quantify capsinoids to provide selected cultivars with high capsinoid contents, which can then be employed as health food product. Quantifying low concentrations of capsinoids from pepper fruit requires a precise and selective analytical technique such as HPLC coupled to electrospray ionization - mass spectrometry, with development of an internal standard essential. In this work, the synthesis method of a novel compound analogue of capsinoids, the (±)-3,4-dimethoxybenzyl-4-methyloctanoate, which could be a suitable internal standard for capsinoid determination by electrospray ionization - mass spectrometry is described. (±)-3,4-dimethoxybenzyl-4-methyloctanoate was stable under the analysis conditions and exerted chemical and physical properties similar to those of capsinoids. This internal standard will provide an accurate capsinoid determination by electrospray ionization - mass spectrometry, thus facilitating the pepper breeding programs, screening pepper cultivars and a better understanding of capsinoid biosynthetic pathway.
Fayos,Barbero,Savirón,Orduna,Durán,Palma,Molinillo,Macías,Barroso,Mallor,Garcés-Claver
p. 87 - 94
(2018)
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One-Pot Biocatalytic In Vivo Methylation-Hydroamination of Bioderived Lignin Monomers to Generate a Key Precursor to L-DOPA
Electron-rich phenolic substrates can be derived from the depolymerisation of lignin feedstocks. Direct biotransformations of the hydroxycinnamic acid monomers obtained can be exploited to produce high-value chemicals, such as α-amino acids, however the reaction is often hampered by the chemical autooxidation in alkaline or harsh reaction media. Regioselective O-methyltransferases (OMTs) are ubiquitous enzymes in natural secondary metabolic pathways utilising an expensive co-substrate S-adenosyl-l-methionine (SAM) as the methylating reagent altering the physicochemical properties of the hydroxycinnamic acids. In this study, we engineered an OMT to accept a variety of electron-rich phenolic substrates, modified a commercial E. coli strain BL21 (DE3) to regenerate SAM in vivo, and combined it with an engineered ammonia lyase to partake in a one-pot, two whole cell enzyme cascade to produce the l-DOPA precursor l-veratrylglycine from lignin-derived ferulic acid.
Birmingham, William R.,Galman, James L.,Parmeggiani, Fabio,Seibt, Lisa,Turner, Nicholas J.
(2022/01/13)

Direct use of the solid waste from oxytetracycline fermentation broth to construct Hf-containing catalysts for Meerwein-Ponndorf-Verley reactions
The oxytetracycline fermentation broth residue (OFR) is an abundant solid waste in the fermentation industry, which is hazardous but tricky to treat. The resource utilization of the waste OFR is still challenging. In this study, a novel route of using OFR was proposed that OFR was used as the organic ligands to construct a new hafnium based catalyst (Hf-OFR) for Meerwein-Ponndorf-Verley (MPV) reactions of biomass-derived platforms. The acidic groups in OFR were used to coordinate with Hf4+, and the carbon skeleton structures in OFR were used to form the spatial network structures of the Hf-OFR catalyst. The results showed that the synthesized Hf-OFR catalyst could catalyze the MPV reduction of various carbonyl compounds under relatively mild reaction conditions, with high conversions and yields. Besides, the Hf-OFR catalyst could be recycled at least 5 times with excellent stability in activity and structures. The prepared Hf-OFR catalyst possesses the advantages of high efficiency, a simple preparation process, and low cost in ligands. The proposed strategy of constructing catalysts using OFR may provide new routes for both valuable utilization of the OFR solid waste in the fermentation industry and the construction of efficient catalysts for biomass conversion.
Chen, Yuxin,Yao, Xuefeng,Wang, Xiaolu,Zhang, Xuefeng,Zhou, Huacong,He, Runxia,Liu, Quansheng
p. 13970 - 13979
(2021/04/22)

Laccase-catalyzed oxidation of allylbenzene derivatives: Towards a green equivalent of ozonolysis
Laccase-based biocatalytic reactions have been tested with and without mediators and optimized in the oxidation of allylbenzene derivatives, such as methyl eugenol taken as a model substrate. The reaction primarily consisted in the hydroxylation of the propenyl side chain, either upon isomerization of the double bond or not. Two pathways were then observed; oxidation of both allylic alcohol intermediates could either lead to the corresponding α,β-unsaturated carbonyl com-pound, or the corresponding benzaldehyde derivative by oxidative cleavage. Such a process consti-tutes a green equivalent of ozonolysis or other dangerous or waste-generating oxidation reactions. The conversion rate was sensitive to the substitution patterns of the benzenic ring and subsequent electronic effects.
Antoniotti, Sylvain,Blerot, Bernard,Chietera, Giorgiana,Lecourt, Mathilde
supporting information

(2021/10/19)

Light-driven MPV-type reduction of aryl ketones/aldehydes to alcohols with isopropanol under mild conditions
Alcohols are versatile structural motifs of pharmaceuticals, agrochemicals and fine chemicals. With respect to green chemistry, the development of more sustainable and cost-efficient processes for converting ketones/aldehydes to alcohols is highly desired. Herein, a direct light-driven strategy for reducing ketones/aldehydes to alcohols using isopropanol as the reducing agent and solvent, in the presence of t-BuOLi, under an air atmosphere at room temperature is developed. This operationally simple light-promoted Meerwein-Ponndorf-Verley (MPV) type reduction can be used to produce various benzylic alcohol derivatives as well as applied to bioactive molecules and PEEK model compounds, demonstrating its application potential.
Cao, Dawei,Xia, Shumei,Pan, Pan,Zeng, Huiying,Li, Chao-Jun,Peng, Yong
supporting information
p. 7539 - 7543
(2021/10/12)

Scope and limitations of biocatalytic carbonyl reduction with white-rot fungi
The reductive activity of various basidiomycetous fungi towards carbonyl compounds was screened on an analytical level. Some strains displayed high reductive activities toward aromatic carbonyls and aliphatic ketones. Utilizing growing whole-cell cultures of Dichomitus albidofuscus, the reactions were up-scaled to a preparative level in an aqueous system. The reactions showed excellent selectivities and gave the respective alcohols in high yields. Carboxylic acids were also reduced to aldehydes and alcohols under the same conditions. In particular, benzoic, vanillic, ferulic, and p-coumaric acid were reduced to benzyl alcohol, vanillin, dihydroconiferyl alcohol and 1-hydroxy-3-(4-hydroxyphenyl)propan, respectively.
Zhuk, Tatyana S.,Skorobohatko, Oleksandra S.,Albuquerque, Wendell,Zorn, Holger
supporting information

(2021/02/02)

Highly efficient Meerwein-Ponndorf-Verley reductions over a robust zirconium-organoboronic acid hybrid
The Meerwein-Ponndorf-Verley (MPV) reaction is an attractive approach to selectively reduce carbonyl groups, and the design of advanced catalysts is the key for these kinds of interesting reactions. Herein, we fabricated a novel zirconium organoborate using 1,4-benzenediboronic acid (BDB) as the precursor for MPV reduction. The prepared Zr-BDB had excellent catalytic performance for the MPV reduction of various biomass-derived carbonyl compounds (i.e., levulinate esters, aldehydes and ketones). More importantly, the number of borate groups on the ligands significantly affected the catalytic activity of the Zr-organic ligand hybrids, owing to the activation role of borate groups on hydroxyl groups in the hydrogen source. Detailed investigations revealed that the excellent performance of Zr-BDB was contributed by the synergetic effect of Zr4+and borate. Notably, this is the first work to enhance the activity of Zr-based catalysts in MPV reactions using borate groups.
Song, Jinliang,Hua, Manli,Huang, Xin,Visa, Aurelia,Wu, Tianbin,Fan, Honglei,Hou, Minqiang,Zhang, Zhaofu,Han, Buxing
p. 1259 - 1265
(2021/02/26)

Erratum: Redox-Noninnocent Ligand-Supported Vanadium Catalysts for the Chemoselective Reduction of C=X (X = O, N) Functionalities (Journal of the American Chemical Society (2019) 141:38 (15230-15239) DOI: 10.1021/jacs.9b07062)
Pages 15232, 15233, and 15236. In the original paper, the doublet wave functions for 21 and 21a/21b were incorrectly (Figure Presented). reported as spin-contaminated in sections 2.3 and 2.8 (Figure 3 and Scheme 9, respectively.) This comes from the incorrectly reported expected eigenvalue of 0.75 for the spin-squared operator ??2? for the antiferromagnetically coupled doublet |↓?L|↑↑?V state (originally given in the Supporting Information). The correct expected eigenvalue for the |↓?L|↑↑?V state should be 1.75. The wave functions for 21 and 21a/21b (eigenvalues 1.79 and 1.77/1.66, respectively) are therefore not spincontaminated. The corrected Figure 3 and Scheme 9 are presented below. A corrected Supporting Information file is also provided. The corrections do not affect any of the conclusions of the Article, but slightly decrease the gap between the quartet and doublet spin surfaces. Scheme 3 has been also corrected to reflect the fact that (CH3)3SiCH2 ? radicals can only react based on spin conservation.
Zhang, Guoqi,Wu, Jing,Zheng, Shengping,Neary, Michelle C.,Mao, Jincheng,Flores, Marco,Trovitch, Ryan J.,Dub, Pavel A.
supporting information
p. 16507 - 16509
(2020/10/14)

Selective production of bio-based aromatics by aerobic oxidation of native soft wood lignin in tetrabutylammonium hydroxide
Aerobic oxidation of native soft wood lignin in an aqueous solution of Bu4NOH facilitates efficient production of vanillin (4-hydroxy-3-methoxybenzaldehyde), which is one of the platform chemicals in industry. Oxidation of Japanese cedar (Cryptomeria japonica) wood flour at 120 °C for 4 h under O2in Bu4NOH-based aqueous solutions produced vanillin in 23.2 wt% yield based on the Klason lignin content of the starting material. This yield was comparable to that in alkaline nitrobenzene oxidation of the same material (27.2%), which indicated that our aerobic oxidation exploited the full potential of the wood flour for vanillin production. Further mechanical investigation with lignin model compounds suggested that the vanillin formation occurred mainly through following successive reactions: alkaline-catalyzed degradation of ?-ether linkages in middle units of lignin polymer to form a glycerol end group, oxidation of the glycerol end group by O2to a HCa?O moiety, and release of vanillin from the HCa?O end. One of the reasons for the high performance of Bu4NOH for the vanillin production was explained by the general understanding in organic chemistry that Bu4OH is a stronger base than simple alkali,e.g.NaOH. The other more fundamental mechanical aspect was that Bu4N+suppressed disproportionation of the vanillin precursor (the CaHO end group) probably due to strong interaction between the cation and the HCa?O end group.
Hosoya, Takashi,Miyafuji, Hisashi,Yamada, Tatsuhiko,Yamamoto, Kohei
p. 19199 - 19210
(2020/06/04)

CNN pincer ruthenium complexes for efficient transfer hydrogenation of biomass-derived carbonyl compounds
The ligand HCNNOMe (6-(4-methoxyphenyl)-2-aminomethylpyridine) is easily prepared from the commercially available 6-(4-methoxyphenyl)pyridine-2-carbaldehyde by the reaction of hydroxylamine and hydrogenation (H2, 1 atm) with Pd/C. The pincer complexes cis-[RuCl(CNNOMe)(PPh3)2] (1) and [RuCl(CNNOMe)(PP)] (PP = dppb, 2; and dppf, 3) are synthesized from [RuCl2(PPh3)3], HCNNOMe and PP (for 2 and 3) in 2-propanol with NEt3 at reflux and are isolated in 85-93% yield. Carbonylation of 1 (CO, 1 atm) gives [RuCl(CNNOMe)(CO)(PPh3)] (4) (79% yield) which cleanly reacts with Na[BArf4] and PCy3, affording the cationic trans-[Ru(CNNOMe)(CO)(PCy3)(PPh3)][BArf4] (5) (92% yield). These robust pincer complexes display remarkably high catalytic activity in the transfer hydrogenation (TH) of lignocellulosic biomass carbonyl compounds, using 2-propanol at reflux in a basic medium (NaOiPr or K2CO3). Thus, furfural, 5-(hydroxymethyl)furfural and Cyrene are reduced to the corresponding alcohols with 2 and 3, at S/C in the range of 10 000-100 000, within minutes or hours (TOF up to 1 500 000 h-1). The monocarbonyl complex 5 was found to be extremely active in the TH of cinnamaldehyde, vanillin derivatives and ethyl levulinate at S/C in the range of 10 000-50 000. Vanillyl alcohol is also obtained by the TH of vanillin with 5 (S/C = 500) in 2-propanol in the presence of K2CO3.
Figliolia, Rosario,Cavigli, Paolo,Comuzzi, Clara,Del Zotto, Alessandro,Lovison, Denise,Strazzolini, Paolo,Susmel, Sabina,Zuccaccia, Daniele,Ballico, Maurizio,Baratta, Walter
supporting information
p. 453 - 465
(2020/01/21)

Microwave-heated γ-Alumina Applied to the Reduction of Aldehydes to Alcohols
The development of cheap and robust heterogeneous catalysts for the Meerwein-Ponndorf-Verley (MPV) reduction is desirable due to the difficulties in product isolation and catalyst recovery associated with the traditional use of homogeneous catalysts for MPV. Herein, we show that microwave heated γ-Al2O3 can be used for the reduction of aldehydes to alcohols. The reaction is efficient and has a broad substrates scope (19 entries). The products can be isolated by simple filtration, and the catalyst can be regenerated. With the use of microwave heating, we can direct the heating to the catalyst rather than to the whole reaction medium. Furthermore, DFT was used to study the reaction mechanism, and we can conclude that a dual-site mechanism is operative where the aldehyde and 2-propoxide are situated on two adjacent Al sites during the reduction. Additionally, volcano plots were used to rationalize the reactivity of Al2O3 in comparison to other metal oxides.
Dhokale, Bhausaheb,Susarrey-Arce, Arturo,Pekkari, Anna,Runemark, August,Moth-Poulsen, Kasper,Langhammer, Christoph,H?relind, Hanna,Busch, Michael,Vandichel, Matthias,Sundén, Henrik
p. 6344 - 6355
(2020/10/28)

Triazole derivative as well as preparation method and application thereof
The invention relates to a triazole derivative as well as a preparation method and application thereof, which belong to the technical field of organic synthetic drugs. The structure of the triazole derivative is shown as a formula I. In the formula I, R1 and R2 are H, Cl, Br,-CF3,-CH(CH3)2 or -OCH3, and R1 and R2 are not H at the same time. R3 is -CH2 or -COCH2; X and Y are N or C, X and Y are not C at the same time, and X and Y are not N at the same time. The triazole derivative disclosed by the invention has a certain inhibition effect on germs of various crop diseases. Small toxic andside effects on plants are achieved. The preparation method of the triazole derivative is simple.
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Paragraph 0081; 0088-0090

(2020/06/09)

Kinetics and Mechanism of the Hydrolysis of Benzyl Ether Bonds in Aqueous–Organic Media
Abstract: Kinetic parameters (rate constant, energy of activation, and entropy of activation) of the acid-catalyzed hydrolysis of the benzyl ethers (3,4-dimethoxyphenyl)-(2-methoxyphenoxy)methane and (4-hydroxy-3-methoxyphenyl)methoxymethane are determined for a wide range of compositions for mixtures of water and organic solvents (dioxane, DMSO, and acetic acid). It is shown that the acid-catalyzed hydrolysis of these benzyl ethers in mixtures of water and aprotic solvents occurs as a reaction of bimolecular nucleophilic substitution. In aqueous acetic acid solutions, the mechanism of hydrolysis can be bimolecular or unimolecular, depending on the structure of the ether and the content of the organic solvent. The effect the solvents have on the rate and mechanism of the studied reaction is discussed in terms of solvation concepts.
Kushner, M. A.,Matusevich, L. G.,Seliverstova, T. S.
p. 310 - 316
(2020/04/10)

A novel hafnium-graphite oxide catalyst for the Meerwein-Ponndorf-Verley reaction and the activation effect of the solvent
Construction and application of novel hydrogenation catalysts is important for the conversion of carbonyl or aldehyde compounds into alcohols in the field of biomass utilization. In this work, a novel, efficient, and easily prepared hafnium-graphite oxide (Hf-GO) catalyst was constructed via the coordination between Hf4+ and the carboxylic groups in GO. The catalyst was applied into the hydrogenation of biomass derived carbonyl compounds via the Meerwein-Ponndorf-Verley (MPV) reaction. The catalyst gave high efficiency under mild conditions. An interesting phenomenon was found whereby the activity of the catalyst increased gradually in the initial stage during reaction. The solvent, isopropanol, was proved to have an activation effect on the catalyst, and the activation effect varied with different alcohols and temperatures. Further characterizations showed that isopropanol played the activation effect via replacing the residual solvent (DMF) in micro- and mesopores during the preparation process, which was hard to be completely removed by common drying process.
Li, Xiaomin,Du, Zhengjiang,Wu, Yi,Zhen, Yadong,Shao, Rixin,Li, Bingqi,Chen, Chengmeng,Liu, Quansheng,Zhou, Huacong
p. 9985 - 9995
(2020/03/26)

In vitro study and structure-activity relationship analysis of stilbenoid derivatives as powerful vasorelaxants: Discovery of new lead compound
The development of vasorelaxant as the antihypertensive drug is important as it produces a rapid and direct relaxation effect on the blood vessel muscles. Resveratrol (RV), as the most widely studied stilbenoid and the lead compound, inducing the excellent vasorelaxation effect through the multiple signalling pathways. In this study, the in vitro vascular response of the synthesized trans-stilbenoid derivatives, SB 1-8e were primarily evaluated by employing the phenylephrine (PE)-precontracted endothelium-intact isolated aortic rings. Herein we report trans-3,4,4′-trihydroxystilbene (SB 8b) exhibited surprisingly more than 2-fold improvement to the maximal relaxation (Rmax) of RV. This article also highlights the characterization of the aromatic protons in terms of their unique splitting patterns in 1H NMR.
Chan, Sock Ying,Loh, Yean Chun,Oo, Chuan Wei,Yam, Mun Fei
(2020/10/12)

Evaluation of Cu(II) bzimpy complexes by 1H-NMR and catalytic activities
Copper(II) complexes (3a–d and 4a–d) containing tridentate 2,6-bis(benzimidazole-2-yl) pyridine (bzimpy) were synthesized and characterized by 1H-NMR, elemental analysis, IR, UV and mass spectroscopy. These complexes were tested as catalysts in transfer hydrogenation (TH). The effects of wingtip substituents on bzimpy ligand to the TH activity of Cu(II) complexes were investigated. Among the catalysts, complex 4d with sterically bulky bzimpy ligand showed the highest catalytic activity in this transformation.
Günnaz, Salih
p. 3014 - 3027
(2020/11/12)

Untangling the active sites in the exposed crystal facet of zirconium oxide for selective hydrogenation of bioaldehydes
The present study reports the influence of the crystal phase, facets, and active sites of zirconium oxide (ZrO2) on the conversion of bio-aldehydes to their corresponding alcohols in isopropanol under mild reaction conditions. Various ZrO2-based catalysts, having different compositions of monoclinic and tetragonal crystal phases, are successfully prepared in the presence of a base via a solvothermal process. From the detailed characterization through XRD, TEM, CO2-TPD, XPS, AES, BET and poisoning studies, M-ZrO2-U-N, synthesized using zirconium oxynitrate and urea as a precursor and precipitant, respectively, in water, possesses a 100% monoclinic crystal phase with a maximum amount of exposed (-111) facets and surface oxygen concentration along with the highest number of basic sites. The catalytic study on the transformation of furfural (FFA) into furfuryl alcohol (FOH) reveals that M-ZrO2-U-N exhibits the best efficiency with a nearly quantitative yield of FOH. On the other hand, T-ZrO2-U-N, synthesized using zirconium oxynitrate and urea as a precursor and precipitant, respectively, in methanol, is found to have a 94.4% tetragonal phase and a 2.2-fold lower number of basic sites in comparison with M-ZrO2-U-N. The catalytic result with T-ZrO2-U-N displays the lowest activity in terms of the FOH yield (8.1%). According to the comparative and systematic catalytic studies with the various ZrO2 catalysts having different amounts of tetragonal and monoclinic phases, the ZrO2 catalyst having a more monoclinic phase with more exposed (-111) facets, basic sites, surface oxygen species and surface area is found to be crucial for the FFA conversion to FOH with high selectivity. M-ZrO2-U-N is found to be stable and recyclable and also shows excellent activity towards the transformation of other bio-aldehydes and ketones into their corresponding alcohols. This journal is
Devi, Mayanglambam Manolata,Kansal, Sushil Kumar,Kumar, Sahil,Saravanamurugan, Shunmugavel
p. 7016 - 7026
(2020/11/09)

Selective hydrogenation of primary amides and cyclic di-peptides under Ru-catalysis
A ruthenium(II)-catalyzed selective hydrogenation of challenging primary amides and cyclic di-peptides to their corresponding primary alcohols and amino alcohols, respectively, is reported. The hydrogenation reaction operates under mild and eco-benign conditions and can be scaled-up.
Subaramanian, Murugan,Sivakumar, Ganesan,Babu, Jessin K.,Balaraman, Ekambaram
supporting information
p. 12411 - 12414
(2020/10/30)

The construction of novel and efficient hafnium catalysts using naturally existing tannic acid for Meerwein-Ponndorf-Verley reduction
The conversion of carbonyl compounds into alcohols or their derivatives via the catalytic transfer hydrogenation (CTH) process known as Meerwein-Ponndorf-Verley reduction is an important reaction in the reaction chain involved in biomass transformation. The rational design of efficient catalysts using natural and renewable materials is critical for decreasing the catalyst cost and for the sustainable supply of raw materials during catalyst preparation. In this study, a novel hafnium-based catalyst was constructed using naturally existing tannic acid as the ligand. The prepared hafnium-tannic acid (Hf-TA) catalyst was characterized by scanning electron microscopy (SEM), transmission electron microscopy (TEM), X-ray diffraction (XRD), Fourier transform infrared spectroscopy (FTIR), and thermogravimetry (TG). Hf-TA was applied in the conversion of furfuraldehyde (FD) to furfuryl alcohol (FA) using isopropanol (2-PrOH) as both the reaction solvent and the hydrogen source. Both preparation conditions and the effects of the reaction parameters on the performance of the catalyst were studied. Under the relatively mild reaction conditions of 70 °C and 3 h, FD (1 mmol) could be converted into FA with a high yield of 99.0%. In addition, the Hf-TA catalyst could be reused at least ten times without a notable decrease in activity and selectivity, indicating its excellent stability. It was proved that Hf-TA could also catalyze the conversion of various carbonyl compounds with different structures. The high efficiency, natural occurrence of tannic acid, and facile preparation process make Hf-TA a potential catalyst for applications in the biomass conversion field.
Deng, Lijuan,Hao, Jianxiu,He, Runxia,Li, Na,Liu, Quansheng,Wang, Xiaolu,Zhao, Hongye,Zhi, Keduan,Zhou, Huacong
p. 6944 - 6952
(2020/03/03)

Paired Electrochemical Reactions and the On-Site Generation of a Chemical Reagent
While the majority of reported paired electrochemical reactions involve carefully matched cathodic and anodic reactions, the precise matching of half reactions in an electrolysis cell is not generally necessary. During a constant current electrolysis almost any oxidation and reduction reaction can be paired, and in the presented work we capitalize on this observation by examining the coupling of anodic oxidation reactions with the production of hydrogen gas for use as a reagent in remote, Pd-catalyzed hydrogenation and hydrogenolysis reactions. To this end, an alcohol oxidation, an oxidative condensation, intramolecular anodic olefin coupling reactions, an amide oxidation, and a mediated oxidation were all shown to be compatible with the generation and use of hydrogen gas at the cathode. This pairing of an electrolysis reaction with the production of a chemical reagent or substrate has the potential to greatly expand the use of more energy efficient paired electrochemical reactions.
Wu, Tiandi,Nguyen, Bichlien H.,Daugherty, Michael C.,Moeller, Kevin D.
supporting information
p. 3562 - 3565
(2019/02/20)

Polypyridyl iridium(III) based catalysts for highly chemoselective hydrogenation of aldehydes
Iridium-catalyzed transfer hydrogenation (TH) of carbonyl compounds using HCOOR (R = H, Na, NH4) as a hydrogen source is a pivotal process as it provides the clean process and is easy to execute. However, the existing highly efficient iridium catalysts work at a narrow pH; thus, does not apply to a wide variety of substrates. Therefore, the development of a new catalyst which works at a broad pH range is essential as it can gain a broader scope of utilization. Here we report highly efficient polypyridyl iridium(III) catalysts, [Ir(tpy)(L)Cl](PF6)2 {where tpy = 2,2′:6′,2′'-Terpyridine, L = phen (1,10-Phenanthroline), Me2phen (4,7-Dimethyl-1,10-phenanthroline), Me4phen (3,4,7,8-Tetramethyl-1,10-phenanthroline), Me2bpy (4,4′-Dimethyl-2–2′-dipyridyl)} for the chemoselective reduction of aldehydes to alcohols in aqueous ethanol and sodium formate as the hydride source. The reaction can be carried out efficiently in broad pH ranges, from pH 6 to 11. These catalysts are air stable, easy to prepare using commercially available starting materials, and are highly applicable for a wide range of substrates, such as electron-rich or deficient (hetero)arenes, halogens, phenols, alkoxy, ketones, esters, carboxylic acids, cyano, and nitro groups. Particularly, acid and hydroxy groups containing aldehydes were reduced successfully in basic and acidic reaction conditions, demonstrating the efficiency of the catalyst in a broad pH range with high conversion rates under microwave irradiation.
Pandrala, Mallesh,Resendez, Angel,Malhotra, Sanjay V.
p. 283 - 288
(2019/09/30)

Preparation process of veratryl alcohol and prepared veratryl alcohol
The invention discloses a preparation process of veratryl alcohol and the prepared veratryl alcohol, and relates to the technical field of preparation of alcohols. The preparation process of the veratryl alcohol comprises the following steps that veratraldehyde, a solvent and a catalyst are uniformly mixed and then subjected to hydrogen reduction to obtain the veratryl alcohol. The preparation process of the veratryl alcohol has the advantages that the veratryl alcohol is directly prepared through hydrogen reduction and hydrogenation and by taking the veratraldehyde as a raw material, therebysignificantly increasing the mass yield of the veratryl alcohol, reducing the content of impurities, and increasing the utilization rate of the raw materials; the veratryl alcohol prepared through thepreparation process has high purity and less impurities; in addition, waste water and waste gas are not generated, the green and environmental protection is achieved, the production efficiency is high, the production cost is low, and the process is simple.
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Paragraph 0119-0199

(2019/06/12)

Hierarchically constructed NiO with improved performance for catalytic transfer hydrogenation of biomass-derived aldehydes
A 3D nano-/micrometer-scaled NiO material with urchin-like structure was prepared via a facile, green synthesis route, and served as a highly efficient and durable catalyst for catalytic transfer hydrogenation (CTH) of bio-based furfural (FF) to furfuryl alcohol (FAOL) using 2-propanol as H-donor and solvent. The as-prepared NiO possessed a good active-site accessibility owing to a high surface area and large amount of acid-base sites, resulting in high FF conversion of 97.3% with 94.2% FAOL yield at 120 °C and 3 h of reaction, which was a superior catalytic performance compared to commercial NiO nanoparticles. Besides, the excellent catalytic performance of the sea urchin-like NiO was validated for gram-scale FAOL synthesis, and recyclability test confirmed the catalyst to be reusable for multiple reaction runs without significant activity loss after intermediary calcination in air. Notably, the introduced catalytic system was also applicable to CTH of alternative bio-derived aldehydes.
He, Jian,Nielsen, Monia Runge,Hansen, Thomas Willum,Yang, Song,Riisager, Anders
p. 1289 - 1300
(2019/03/11)

A method of synthesis of primary alcohol (by machine translation)
The invention discloses a method for synthesizing a primary alcohol, using transition metal catalysis, the use of isopropanol as a hydrogen source to synthesize primary alcohol, the reaction not only using a cheap, environmental protection of isopropanol as a hydrogen source and solvent, and has high yield, environmental protection and the like, so that the reaction has broad prospects for development. (by machine translation)
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Paragraph 0055; 0056; 0057; 0058; 0059

(2019/03/17)

Surfactant-assisted synthesis of mesoporous hafnium- imidazoledicarboxylic acid hybrids for highly efficient hydrogen transfer of biomass-derived carboxides
Catalytic transfer hydrogenations of biomass-derived carbonyl compounds to produce corresponding alcohols are important pathway for biomass transformation. Herein, a facile route was developed to synthesize the surfactant-assisted heterogeneous acid-base bifunctional 4,5-imidazoledicarboxylic acid-hafnium hybrid catalyst (Hf-H3IDC-T) by hydrothermal self-assembly method. The as-prepared Hf-H3IDC-T was characterized by SEM and TEM, FT-IR spectra, N2 adsorption-desorption, X-ray diffraction patterns (XRD), X-ray photoelectron spectroscopy (XPS), Thermogravimetry analysis (TG), NH3/CO2-TPD, NMR, GC[sbnd]MS, ICP-OES and elemental analysis. Hf-H3IDC-T hybrid had mesoporous structure and acid-base couple sites. A quantitative yield (99.2%) of furfuryl alcohol (FFA) was obtained from furfural (FUR) over Hf-H3IDC-T using 2-propanol as the hydrogen source under mild conditions. It's found that the amino groups on the imidazole ring is beneficial to enhance the base sites of catalyst. Meanwhile, the addition of hexadecyl trimethyl ammonium bromide (CTAB) as template agents can improve the specific surface area of the catalyst. Dynamic analysis showed that the apparent activation energy of FUR reduction was as low as 50.89 kJ / mol. The as-prepared catalyst has good stability and can be recycled. Finally, the catalyst also has a good catalytic effect on the hydrogenation reaction of aldehydes and ketones of biomass-derived compounds.
Dai, Fanglin,Zhou, Shenghui,Qin, Xingzhen,Liu, Detao,Qi, Haisong
(2019/09/30)

Design, synthesis and antitumour and anti-angiogenesis evaluation of 22 moscatilin derivatives
Two series of moscatilin derivatives were designed, synthesized and evaluated as anti-tumor and anti-angiogenesis agents. Most of these compounds showed moderate-to-obvious cytotoxicity against five cancer cell lines (A549, HepG2, MDA-MB-231, MKN-45, HCT116). Among these cell lines, compounds had obvious effects on HCT116. Especially for 8Ae, the IC50 was low to 0.25 μM. 8Ae can inhibit the viability and induce the apoptosis of HCT116 cells but exhibit no cytotoxic activity in noncancerous NCM460 colon cells. 8Ae can also arrest the G2/M cell cycle in HCT116 cells by inhibiting the α-tubulin expression. Zebrafish bioassay-guided screen showed the 22 moscatilin derivatives had potent anti-angiogenic activities and compound 8Ae had better activities than positive compound. Molecular docking indicated 8Ae interacted with tubulin at the affinity of ?7.2 Kcal/mol. In conclusion, compound 8Ae was a potential antitumor and anti-angiogenesis candidate for further development.
Guan, Li,Zhou, Junting,Lin, Qinghua,Zhu, Huilin,Liu, Wenyuan,Liu, Baolin,Zhang, Yanbo,Zhang, Jie,Gao, Jing,Feng, Feng,Qu, Wei
p. 2657 - 2665
(2019/05/01)

Iridium-catalysed primary alcohol oxidation and hydrogen shuttling for the depolymerisation of lignin
Lignin is a potentially abundant renewable resource for the production of aromatic chemicals, however its selective depolymerisation is challenging. Here, we report a new catalytic system for the depolymerisation of lignin to novel, non-phenolic monoaromatic products based on the selective β-O-4 primary alcohol dehydrogenation with a Cp?Ir-bipyridonate catalyst complex under basic conditions. We show that this system is capable of promoting the depolymerisation of model compounds and isolated lignins via a sequence of selective primary alcohol dehydrogenation, retro-aldol (Cα-Cβ) bond cleavage and in situ stabilisation of the aldehyde products by transfer (de)hydrogenation to alcohols and carboxylic acids. This method was found to give good to excellent yields of cleavage products with both etherified and free-phenolic lignin model compounds and could be applied to real lignin to generate a range of novel non-phenolic monomers including diols and di-acids. We additionally show, by using the same catalyst in a convergent, one-pot procedure, that these products can be selectively channelled towards a single di-acid product, giving much simpler product mixtures as a result.
Lancefield, Christopher S.,Teunissen, Lucas W.,Weckhuysen, Bert M.,Bruijnincx, Pieter C. A.
supporting information
p. 3214 - 3221
(2018/07/31)

Synthetic method for dihydrostilbenes and anti-inflammatory compounds containing thereof
The present invention aims to provide an effective anti-inflammatory agent without side effects. The present inventors have invented a method for efficiently synthesizing dihydrostilbene and derivatives (compounds 1 to 5) from starting materials at a high yield. In addition, the anti-inflammatory effects were evaluated in LPS-induced RAW-264.7 macrophages. The compounds of dihydrostilbene do not exhibit cytotoxicity and are shown to weakly or well inhibit nitric oxide production induced by LPS at the concentration of 10 andmu;M.COPYRIGHT KIPO 2018
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Paragraph 0104; 0137; 0138; 0141; 0143; 0144

(2018/05/03)

Synthesis of (+)-salvianolic acid A from sodium Danshensu
(+)-Salvianolic acid A, one of the most active components in the traditional Chinese medicine Danshen, has been synthesized over 10 steps in 6.5% overall yield. Starting from inexpensive ortho-vanillin and sodium Danshensu (synthesized via asymmetric catalysis in our group), the process consists of the following: A Wittig reaction that gives the desire product with absolute E-configuration, a demethylation reaction with AlCl3 in a satisfactory yield, and a practical deprotection of allylic groups to afford the terminal product (+)-salvianolic acid A. The current synthetic technology possesses the advantages of using inexpensive starting materials, mild reaction conditions and has the potential for use in large scale synthesis.
Xu, Kai,Liu, Hao,Liu, Delong,Sheng, Cheng,Shen, Jiefeng,Zhang, Wanbin
supporting information
p. 5996 - 6002
(2018/09/06)

Transfer Hydrogenation of Aldehydes and Ketones with Isopropanol under Neutral Conditions Catalyzed by a Metal-Ligand Bifunctional Catalyst [Cp?Ir(2,2′-bpyO)(H2O)]
A Cp?Ir complex bearing a functional bipyridonate ligand [Cp?Ir(2,2′-bpyO)(H2O)] was found to be a highly efficient and general catalyst for transfer hydrogenation of aldehydes and chemoselective transfer hydrogenation of unsaturated aldehydes with isopropanol under neutral conditions. It was noteworthy that many readily reducible or labile functional groups such as nitro, cyano, ester, and halide did not undergo any change under the reaction conditions. Furthermore, this catalytic system exhibited high activity for transfer hydrogenation of ketones with isopropanol. Notably, this research exhibited new potential of metal-ligand bifunctional catalysts for transfer hydrogenation.
Wang, Rongzhou,Tang, Yawen,Xu, Meng,Meng, Chong,Li, Feng
p. 2274 - 2281
(2018/02/23)

Formal total synthesis of salvianolic acid N
An efficient synthetic pathway for the total synthesis of salvianolic acid N has been reported. The key reaction steps, the Wittig reaction for Z-stereoselectivity and an intramolecular cyclization for a seven membered ring skeleton, have been optimized to improve the synthetic feasibility and provide the best conditions in terms of yield. Moreover, a notable reaction is the reaction of the deprotected allylic group with Pd catalyst. An improved overall yield of 11% has been achieved for salvianolic acid N starting from 3,4-dimethoxybenzaldehyde in 11 steps.
Wu, Kong,Xie, Zhong Pao,Cui, Dong-Mei,Zhang, Chen
p. 832 - 837
(2018/02/09)

Heterogenization of cobalt nanoparticles on hollow carbon capsules: Lab-in-capsule for catalytic transfer hydrogenation of carbonyl compounds
Incorporation of cobalt nanoparticles (Co NPs) in porous iron oxide nanospheres (Fe3O4 NSs) templated, glucose derived hollow carbon capsules (HCCs), with an objective to achieve activity and stability simultaneously, facilitates higher catalytic activity of Co NPs in transfer hydrogenation of ketones and aldehydes. A variety of ketones and aldehydes are hydrogenated successfully with excellent yields and high turnover number (TON). This system constitutes one of the most general, heterogeneous, highly stable catalyst, which does not require additives for activation and employs mild reaction conditions. Other significant advantages are low Co content (0.38 mol%) for a catalytic hydrogenation reaction, functional-group tolerance, inexpensive, environmentally benign nature and reusability.
Kumar, Basuvaraj Suresh,Amali, Arlin Jose,Pitchumani, Kasi
p. 153 - 161
(2018/03/01)

Magnetic nickel ferrite nanoparticles as highly durable catalysts for catalytic transfer hydrogenation of bio-based aldehydes
Magnetic nickel ferrite (NiFe2O4) nanoparticles were exploited as stable and easily separable heterogeneous catalysts for catalytic transfer hydrogenation (CTH) of furfural to furfuryl alcohol with 2-propanol as both the hydrogen source and the solvent providing 94% product yield at 180 °C after 6 h of reaction. The magnetic properties of the catalysts provided facile recovery using an external magnet after reaction allowing it to be reused in five reaction cycles without loss of catalytic performance. Importantly, the NiFe2O4 nanoparticles were also applicable to CTH of other alkenyl/allyl/aromatic aldehydes affording over 94% selectivity towards the targeted alcohol products, thus being attractive as highly universal catalysts for CTH of aldehydes.
He, Jian,Yang, Song,Riisager, Anders
p. 790 - 797
(2018/02/14)

Nitrogen-containing heterocycle derivatives and applications thereof
The invention discloses nitrogen-containing heterocycle derivatives and applications thereof, relates to compounds of a general formula (V), a preparing method thereof and applications of the compounds in medicines, and more particularly relates to compound derivatives of compounds shown as the general formula (V), a preparing method thereof and uses of the derivatives in medicines preventing andtreating hyperlipemia, hypercholesterolemia, hypertriglyceridemia, fatty degeneration of liver, diabetes mellitus type 2, hyperglycemia, obesity or insulin resistance and metabolic syndrome and resisting antitumor, with the derivatives being adopted as therapeutic agents. The compounds disclosed by the invention can also reduce total cholesterol, LDL-cholesterol and triglyceride, can increase liver LDL receptor expression, and inhibit PCSK9 expression.
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(2018/03/24)

Design, synthesis and biological evaluation of novel pyrimidinedione derivatives as DPP-4 inhibitors
A series of novel pyrimidinedione derivatives were designed and evaluated for in vitro dipeptidyl peptidase-4 (DPP-4) inhibitory activity and in vivo anti-hyperglycemic efficacy. Among them, the representative compounds 11, 15 and 16 showed excellent inhibitory activity of DPP-4 with IC50 values of 64.47 nM, 188.7 nM and 65.36 nM, respectively. Further studies revealed that compound 11 was potent in vivo hypoglycemic effect. The structure–activity relationships of these pyrimidinedione derivatives had been discussed, which would be useful for developing novel DPP-4 inhibitors as treating type 2 diabetes.
Li, Ning,Wang, Li-Jun,Jiang, Bo,Guo, Shu-Ju,Li, Xiang-Qian,Chen, Xue-Chun,Luo, Jiao,Li, Chao,Wang, Yi,Shi, Da-Yong
supporting information
p. 2131 - 2135
(2018/05/25)

Novel leucine ureido derivatives as aminopeptidase N inhibitors using click chemistry
The over-expression of aminopeptidase N on diverse malignant cells is associated with the tumor angiogenesis and metastasis. In this report, one new series of leucine ureido derivatives containing the triazole moiety was designed, synthesized and evaluated as APN inhibitors. Among them, compound 13v showed the best APN inhibition with an IC50 value of 0.089 ± 0.007 μM, which was two orders of magnitude lower than that of bestatin (IC50 = 9.4 ± 0.5 μM). Compound 13v also showed dose-dependent anti-angiogenesis activities. Even at the lower concentration (10 μM), compound 13v presented similar anti-angiogenesis activity compared with bestatin at 100 μM in both the human umbilical vein endothelial cells (HUVECs) capillary tube formation assay and the rat thoracic aorta rings test. Moreover, compared with bestatin, 13v exhibited comparable, if not better in vivo anti-metastasis activity in a mouse H22 pulmonary metastasis model.
Cao, Jiangying,Ma, Chunhua,Zang, Jie,Gao, Shuai,Gao, Qianwen,Kong, Xiujie,Yan, Yugang,Liang, Xuewu,Ding, Qin'ge,Zhao, Chunlong,Wang, Binghe,Xu, Wenfang,Zhang, Yingjie
p. 3145 - 3157
(2018/06/01)

In situ MnOx/N-doped carbon aerogels from cellulose as monolithic and highly efficient catalysts for the upgrading of bioderived aldehydes
Herein, we report a sustainable route to in situ synthesize a monolithic MnOx/N-doped carbon aerogel catalyst (Mn-NCA) by pyrolysing MnO(OH)2-cellulose aerogel precursors based on an alkali-urea aqueous system. The as-obtained Mn-NCA showed highly efficient catalytic activity for the transfer hydrogenation of a broad range of biomass-derived aldehydes, yielding 90-100% conversion and 64-100% selectivity to the corresponding alcohols under mild conditions in an oven without agitation. A combination of controlled experiments and detailed characterization studies indicated that the superior performance of Mn-NCA is attributed to the monolithic three-dimensional (3D) hierarchical porous architecture and the synergistic effects between homogeneously dispersed MnOx nanoparticles (NPs) and urea-derived basic sites. The monolithic feature of Mn-NCA exhibits superior dispersibility and separability compared to conventional centrifugation and filtration techniques in a powdery catalytic system. Moreover, a possible reaction mechanism is proposed. Our work provides a new method for developing highly efficient monolithic catalysts from renewable biopolymers for biomass valorization.
Zhou, Shenghui,Chen, Guixian,Feng, Xiao,Wang, Ming,Song, Tao,Liu, Detao,Lu, Fachuang,Qi, Haisong
p. 3593 - 3603
(2018/08/17)

Discovery of boron-containing compounds as Aβ aggregation inhibitors and antioxidants for the treatment of Alzheimer's disease
A novel series of boron-containing compounds were designed, synthesized and evaluated as multi-target-directed ligands against Alzheimer's disease. The biological activity results demonstrated that these compounds possessed a significant ability to inhibit self-induced Aβ aggregation (20.5-82.8%, 20 μM) and to act as potential antioxidants (oxygen radical absorbance capacity assay using fluorescein (ORAC-FL) values of 2.70-5.87). In particular, compound 17h is a potential lead compound for AD therapy (IC50 = 3.41 μM for self-induced Aβ aggregation; ORAC-FL value = 4.55). Compound 17h also functions as a metal chelator. These results indicated that boron-containing compounds could be new structural scaffolds for the treatment of AD.
Lu, Chuan-Jun,Hu, Jinhui,Wang, Zechen,Xie, Shishun,Pan, Tingting,Huang, Ling,Li, Xingshu
p. 1862 - 1870
(2018/11/24)

A rapid, solvent-free deprotection of methoxymethyl (MOM) ethers by pTSA; An eco-friendly approach
Background: Ease of preparation and alkaline stability of methoxymethyl (MOM) makes it an important hydroxyl protecting group. A number of methods are available for the deprotection of MOM. Though the methods are good in general, they use solvents, require prolonged reaction time and tedious work up. A solvent free, solid phase, fast deprotection of MOM has been developed and is the major theme of this paper. Methods: A mixture of MOM protected compounds and pTSA is triturated in a mortar (5 min) and left at room temperature for 30 min. On addition of water (4°C), pTSA, methanol and formaldehyde dissolved leaving the products as precipitates. Results: A series of different MOM ethers were deprotected by this method in good to excellent yield (85-98%). The compatibility of MOM in the presence of other protections such as methoxyl, benzyl, ester, amide, allyl and lactone was also established. Acetate protection is not stable under these conditions. Conclusion: An efficient, selective and high yielding deprotection MOM groups by pTSA under solvent free condition is described. The process is environment friendly since no solvent was used in the deprotection process. The reaction conditions are mild and should be useful for the deprotection of MOM derivatives of complex and labile molecules.
Pandurangan, Nanjan
p. 231 - 235
(2017/07/15)

Orderly Layered Zr-Benzylphosphonate Nanohybrids for Efficient Acid–Base-Mediated Bifunctional/Cascade Catalysis
The development of functional metal–organic materials that are robust and active for bifunctional/cascade catalysis is of great significance. Herein, a series of mesoporous and orderly layered nanohybrids were synthesized for the first time through simple and template-free assembly of ortho-, meta-, or para-xylylenediphosphonates (o-, p-, or m-PhP) containing zirconium. It was found that m-PhPZr nanoparticles (20–50 nm) with mesopores centered at 7.9 nm and high Lewis acid–base site ratio (1:0.7) showed excellent performance under mild conditions (as low as 82 °C) in transfer hydrogenation of carbonyl compounds, including bioaldehydes and alcohols, with near quantitative yields and little Zr leaching. Isotopic labeling studies indicated the occurrence of direct hydrogen transfer rather than metal hydride route by bifunctional catalysis. Lewis acidic (Zr) and basic (PO3) centers of the heterogeneous catalyst were further revealed to play a synergistic role in one-pot cascade transformations, for example, of ethyl levulinate to γ-valerolactone and glucose to 5-hydroxymethylfurfural.
Li, Hu,Fang, Zhen,He, Jian,Yang, Song
p. 681 - 686
(2017/03/01)

Photocatalytic Decarboxylative Hydroxylation of Carboxylic Acids Driven by Visible Light and Using Molecular Oxygen
This paper discloses the first example of photocatalytic direct decarboxylative hydroxylation of carboxylic acids. It enables the conversion of a variety of readily available carboxylic acids to alcohols in moderate to high yields. This unprecedented protocol is accomplished under extremely mild reaction conditions using molecular oxygen (O2) as a green oxidant and using visible light as a driving force.
Song, Hai-Tao,Ding, Wei,Zhou, Quan-Quan,Liu, Jing,Lu, Liang-Qiu,Xiao, Wen-Jing
p. 7250 - 7255
(2016/08/30)

CSJ acting as a versatile highly efficient greener resource for organic transformations
Simple, new, greener and efficient alternatives to the existing protocols have been developed for the reduction of aromatic aldehydes to their corresponding alcohols, decarboxylation of substituted benzoic acids (C6-C1) and substituted cinnamic acids (C6-C3) with a hydroxyl group at the para position with respect to the acid group to corresponding phenolic compounds and vinyl phenols respectively by using a natural feedstock, cucumber juice (CSJ), which acts as a greener solvent system, performing a substrate-selective reaction. Additionally, the hydrolysis of the acetyl as well as the benzoyl group of aromatic compounds has been carried out to afford excellent yield by CSJ.
Maity, Himadri Sekhar,Misra, Kaushik,Mahata, Tanushree,Nag, Ahindra
p. 24446 - 24450
(2016/03/15)

Dihydrostilbenes and diarylpropanes: Synthesis and in vitro pharmacological evaluation as potent nitric oxide production inhibition agents
An efficient synthesis of dihydrostilbenes (1–5) and diarylpropanes (6–10) is achieved from the commercially available starting materials and Wittig-Horner reaction, Claisen–Schmidt condensation and hydrogenation as key steps. Later, their nitric oxide (NO) production inhibition effects were evaluated in lipopolysaccharide (LPS)-induced RAW-264.7 macrophages as an indicator of anti-inflammatory activity. All the tested compounds significantly decreased NO production in a concentration-dependent manner except compounds 2, 6 and 8 and did not show notable cytotoxicity except compound 1. Two compounds i.e., compound 9 (hindsiipropane B) (100%; IC50?=?1.84?μM) possessed the most potent NO inhibitory activity which was even stronger than the positive control, L-NMMA (90.1%; IC50?=?2.73?μM) followed by compound 4 (75.5%; IC50?=?2.98?μM) at 10?μM concentration and this finding was also further correlated by suppressed expression of LPS stimulated inducible NO synthase. Our study revealed that compound 9, a 1,3-diarylpropane scaffold with 3″,4″-dimethoxyphenyl and 3′,4′-dihydroxy-2′-methoxyphenyl motifs could be considered as potential compound or lead compound for further development of NO production-targeted anti-inflammatory agents.
Jang, Ha Young,Park, Hyeong Jin,Damodar, Kongara,Kim, Jin-Kyung,Jun, Jong-Gab
supporting information
p. 5438 - 5443
(2016/11/09)

Selective acetylation of primary alcohols by ethyl acetate
A KOtBu and ethyl acetate mediated efficient methodology has been developed for the acetylation of primary and secondary alcohols where ethyl acetate is the source of acetyl group. The reaction is fast, mild, efficient, and highly selective towards the primary alcohols.
Singha, Raju,Ray, Jayanta K.
supporting information
p. 5395 - 5398
(2016/11/11)

Acid-base bifunctional zirconium N-alkyltriphosphate nanohybrid for hydrogen transfer of biomass-derived carboxides
Catalytic transfer hydrogenation (CTH) reactions are efficient transformation routes to upgrade biobased chemicals. Herein, we report a facile and template-free route to synthesize a series of heterogeneous nitrogen-containing alkyltriphosphonatemetal hybrids with enhancive Lewis acid and base sites, and their catalytic activity in converting biomass-derived carbonyl compounds to corresponding alcohols in 2-propanol. Particularly, a quantitative yield of furfuryl alcohol (FFA) was obtained from furfural (FUR) over organotriphosphate-zirconium hybrid (ZrPN) under mild conditions. The presence of Lewis basic sites adjacent to acid sites with an appropriate base/acid site ratio (1:0.7) in ZrPN significantly improved the yield of FFA. Mechanistic studies for the transformation of FUR to FFA with ZrPN in 2-propanol-d8 evidently indicate CTH reaction proceeding via a direct intermolecular hydrogen transfer route. It was also found that ZrPN could catalyze isomerization of C3-C6 aldoses to ketoses involving intramolecular hydrogen transfer in water.
Li, Hu,He, Jian,Riisager, Anders,Saravanamurugan, Shunmugavel,Song, Baoan,Yang, Song
p. 7722 - 7727
(2018/05/22)

Ruthenium-Catalyzed C-C bond cleavage in lignin model substrates
Ruthenium-triphos complexes exhibited unprecedented catalytic activity and selectivity in the redox-neutral C-C bond cleavage of the β-O-4 lignin linkage of 1,3-dilignol model compounds. A mechanistic pathway involving a dehydrogenation-initiated retro-aldol reaction for the C-C bond cleavage was proposed in line with experimental data and DFT calculations.
Vom Stein, Thorsten,Den Hartog, Tim,Buendia, Julien,Stoychev, Spas,Mottweiler, Jakob,Bolm, Carsten,Klankermayer, Jürgen,Leitner, Walter
supporting information
p. 5859 - 5863
(2015/05/13)

Chemoselective deprotection and deprotection with concomitant reduction of 1,3-dioxolanes, acetals and ketals using nickel boride
An efficient and mild methodology for the reductive deprotection of 1,3-dioxolanes, acetals and ketals to the corresponding aldehydes/ketones and also deprotection with concomitant reduction to the corresponding alcohols has been achieved in quantitative yields using nickel boride generated in situ from nickel chloride and sodium borohydride in methanol. The reactions are chemoselective as halo, alkoxy and methylenedioxy groups are unaffected.
Khurana, Jitender M.,Dawra, Kiran,Sharma, Purnima
p. 12048 - 12051
(2015/02/19)

FeCl3-catalyzed self-cleaving deprotection of methoxyphenylmethyl-protected alcohols
4-Methoxyphenylmethyl ethers are widely utilized as alcohol protecting groups. FeCl3 effectively catalyzes the deprotection of methoxyphenylmethyl-type ethers in a self-cleaving manner to produce oligomeric derivatives and alcohols. Remarkably, the highly pure mother alcohols can be obtained without silica gel column chromatography by using the 2,4-dimethoxyphenylmethyl group as a protective group.
Sawama, Yoshinari,Masuda, Masahiro,Asai, Shota,Goto, Ryota,Nagata, Saori,Nishimura, Shumma,Monguchi, Yasunari,Sajiki, Hironao
supporting information
p. 434 - 437
(2015/03/03)

Highly chemoselective hydrogenation of active benzaldehydes to benzyl alcohols catalyzed by bimetallic nanoparticles
By using novel Pd/Ni bimetallic nanoparticles as a catalyst, the active benzaldehydes were hydrogenated to the corresponding benzyl alcohols as unique products in practical quantitative yields. The undesired catalytic hydrogenolysis of the benzyl alcohol was inhibited completely. By using this hydrogenation as a key step, the total synthesis of the natural product gastrodin was achieved with less total steps and a higher total yield.
Liu, Chulong,Bao, Hailin,Wang, Dingsheng,Wang, Xinyan,Li, Yadong,Hu, Yuefei
p. 6460 - 6462
(2015/11/16)

Organoborane-Catalyzed Hydrogenation of Unactivated Aldehydes with a Hantzsch Ester as a Synthetic NAD(P)H Analogue
We have developed a method for the hydrogenation of unactivated aldehydes, using a Hantzsch ester as a NAD(P)H analogue in the presence of an electron-deficient triarylborane as a Lewis acid catalyst. Thus, tris[3,5-bis(trifluoromethyl)phenyl]borane efficiently catalyzes the hydrogenation of aliphatic aldehydes with a Hantzsch ester in 1,4-dioxane at 100 °C to give the corresponding aliphatic primary alcohols in up to 97% yield. Aromatic aldehydes also undergo the hydrogenation, even at 25 °C, to furnish the corresponding aromatic primary alcohols in up to 100% yield.
Hamasaka, Go,Tsuji, Hiroaki,Uozumi, Yasuhiro
supporting information
p. 2037 - 2041
(2015/09/01)