93793-62-5Relevant academic research and scientific papers
Manganese-Catalyzed Hydrogenation of Sclareolide to Ambradiol
Zubar, Viktoriia,Lichtenberger, Niels,Schelwies, Mathias,Oeser, Thomas,Hashmi, A. Stephen K.,Schaub, Thomas
, (2021/11/16)
The hydrogenation of (+)-Sclareolide to (?)-ambradiol catalyzed by a manganese pincer complex is reported. The hydrogenation reaction is performed with an air- and moisture-stable manganese catalyst and proceeds under relatively mild reaction conditions at low manganese and base loadings. A range of other esters could be successfully hydrogenated leading to the corresponding alcohols in good to quantitative yields using this easy-to-make catalyst. A scale-up experiment was performed leading to 99.3 % of the isolated yield of (?)-Ambradiol.
Highly effective and chemoselective hydrodeoxygenation of aromatic alcohols
Han, Buxing,He, Mingyuan,Mei, Xuelei,Wu, Haihong,Wu, Wei,Xu, Caiyun,Zhai, Jianxin,Zhang, Kaili,Zhang, Zhanrong,Zheng, Bingxiao
, p. 1629 - 1635 (2022/02/21)
Effective hydrodeoxygenation (HDO) of aromatic alcohols is very attractive in both conventional organic synthesis and upgrading of biomass-derived molecules, but the selectivity of this reaction is usually low because of the competitive hydrogenation of the unsaturated aromatic ring and the hydroxyl group. The high activity of noble metal-based catalysts often leads to undesired side reactions (e.g., saturation of the aromatic ring) and excessive hydrogen consumption. Non-noble metal-based catalysts suffer from unsatisfied activity and selectivity and often require harsh reaction conditions. Herein, for the first time, we report chemoselective HDO of various aromatic alcohols with excellent selectivity, using porous carbon-nitrogen hybrid material-supported Co catalysts. The C-OH bonds were selectively cleaved while leaving the aromatic moiety intact, and in most cases the yields of targeted compounds reached above 99% and the catalyst could be readily recycled. Nitrogen doping on the carbon skeleton of the catalyst support (C-N matrix) significantly improved the yield of the targeted product. The presence of large pores and a high surface area also improved the catalyst efficiency. This work opens the way for efficient and selective HDO reactions of aromatic alcohols using non-noble metal catalysts.
Platinum thiolate complexes supported by PBP and POCOP pincer ligands as efficient catalysts for the hydrosilylation of carbonyl compounds
Chang, Jiarui,Chen, Xuenian,Xue, Man-Man,Zhang, Jie
supporting information, p. 2304 - 2312 (2022/02/21)
Diphosphino-boryl-based PBP pincer platinum thiolate complexes, [Pt(SR){B(NCH2PtBu2)2-1,2-C6H4}] (R = H, 1a; Ph, 1b), and benzene-based bisphosphinite POCOP pincer platinum thiolate complexes, [Pt(SR)(tBu2PO)2-1,3-C6H3] (R = H, 2a; Ph, 2b), were prepared
Solvent effect on the rate and direction of furfural transformations during hydrogenation over the Pd/C catalyst
Belskaya, O. B.,Likholobov, V. A.,Mironenko, R. M.
, p. 64 - 69 (2022/02/25)
The rate and directions of transformations during the liquid-phase hydrogenation of furfural with molecular hydrogen in the presence of the 5%Pd/C catalyst (at 423 K, 3 MPa) depend substantially on the chemical nature of the solvent. The main products of
High-Temperature Synthesis of Carbon-Supported Bimetallic Nanocluster Catalysts by Enlarging the Interparticle Distance
Zuo, Lu-Jie,Xu, Shi-Long,Wang, Ao,Yin, Peng,Zhao, Shuai,Liang, Hai-Wei
supporting information, p. 2719 - 2723 (2022/02/16)
Supported bimetallic nanoparticle catalysts with small size have attracted wide research attention in catalysis but are difficult to synthesize because high-temperature annealing required for alloying inevitably accelerates metal sintering and leads to larger particles. Here, we report a simple and scalable critical interparticle distance method for the synthesis of a family of bimetallic nanocluster catalysts with an average particle size of only 1.5 nm by using large-surface-area carbon black supports at high temperatures, which consist of 12 diverse combinations of 3 noble metals (Pt, Ru, and Rh) and 4 other metals (Cr, Fe, Zr, and Sn). In this strategy, high-temperature treatments ensure the formation of alloyed bimetallic nanoparticles and enlargement of the interparticle distance on high-surface-area supports significantly suppresses metal sintering. The prepared ultrafine Pt2Sn and RuSn nanocluster catalysts exhibited enhanced performance in catalyzing the synthesis of aromatic secondary amines and the selective hydrogenation of furfural, respectively.
Transfer hydrogenation of furfural to furfuryl alcohol over modified Zr-based catalysts using primary alcohols as H-donors
Wang, Yantao,Zhao, Deyang,Liang, Rui,Triantafyllidis, Konstantinos S.,Yang, Weiran,Len, Christophe
, (2020/12/07)
Catalytic transfer hydrogenation is gaining increasing attention as a promising alternative to conventional hydrogenation with H2. In present work, a series of modified Zr-based catalysts were synthesized and tested for furfural catalytic transfer hydrogenation into furfuryl alcohol (FA). The results indicated that more than 13 % of furfural conversion and furfuryl alcohol yield could be achieved with modified zirconium hydroxide (mZrH) at 140 °C when compared with zirconium hydroxide (ZrH) using ethanol as H-donor and solvent in continuous flow regime, and the activity could be further enhanced by increasing the reaction temperature or Ru loading on the catalyst. The best result of 92 % furfural conversion with ～99 % FA selectivity was obtained at 150 °C with 6% Ru/mZrH as catalyst, and the productivity of FA is 5.5 mmol g?1 h?1 which is 2 times higher than that reported with ZrH in batch. Moreover, long-term stability study of the catalysts indicated that 6% Ru/mZrH not only performs a better activity, but also a better stability than 6% Ru/ZrH. Characterizations of the catalysts by BET, XRD, EA, IR, SEM-EDS, XPS and CO2 adsorption indicated that zirconium hydroxide (ZrH) was successfully modified with hydroxylamine, leading to significantly change of its morphology and basic sites. And the deactivation of the catalysts was due to both the leaching of Ru and the deposition of side-products on its surface.
Pd-Catalysed Decarbonylation Free Approach to Carbonylative Esterification of 5-HMF to Its Aryl Esters Synthesis Using Aryl Halides and Oxalic Acid as C1 Source
Singh Chauhan, Arvind,Kumar, Ajay,Kumar Sharma, Ajay,Das, Pralay
, p. 12971 - 12975 (2021/08/06)
A decarbonylation free, polystyrene-supported, Pd (Pd@PS)-catalysed carbonylative esterification of the hydroxy group of 5-hydroxymethyl furfural (5-HMF) to its corresponding aryl esters has been developed. The use of Pd@PS, oxalic acid as CO source, and aryl halides was first explored for the aryl ester of 5-HMF synthesis. Here, we investigated the vital role of a polystyrene support to avoid the commonly known decarbonylation of 5-HMF. The reaction exhibits vast substrate scope with comparably good yield and catalyst recyclability.
PNO ligand containing planar chiral ferrocene and application thereof
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Paragraph 0114-0118, (2021/06/21)
The invention discloses a PNO ligand containing planar chiral ferrocene and application thereof. The PNO ligand containing planar chiral ferrocene is a planar chiral ferrocene-containing and phenol-containing PNO ligand as shown in a general formula (I) or (II) which is described in the specification, or a planar chiral ferrocene-containing and aryl-phosphoric-acid-containingPNO ligand containing as shown in a general formula (III) or (IV) which is described in the specification, or a planar chiral ferrocene-containing and carbon-chiral-phenol-containingPNO ligand as shown in a general formula (V) or (VI) which is described in the specification. The invention provides tridentate PNO ligands and processes for their complexation with transition metal salts or transition metal complexes; the introduction of salicylaldehyde and derivatives thereof, which are simple and easy to obtain, enables the ligands to have a bifunctionalization effect, and -OH in a formed catalyst has stronger acidity and is beneficial to combination with N/O in polar double bonds. Therefore, due to the bifunctionalization effect of the catalyst, the interaction between the catalyst and a substrate can be greatly improved, so a reaction can obtain higher catalytic activity and stereoselectivity.
Me3SI-promoted chemoselective deacetylation: a general and mild protocol
Gurawa, Aakanksha,Kashyap, Sudhir,Kumar, Manoj
, p. 19310 - 19315 (2021/06/03)
A Me3SI-mediated simple and efficient protocol for the chemoselective deprotection of acetyl groups has been developedviaemploying KMnO4as an additive. This chemoselective deacetylation is amenable to a wide range of substrates, tolerating diverse and sensitive functional groups in carbohydrates, amino acids, natural products, heterocycles, and general scaffolds. The protocol is attractive because it uses an environmentally benign reagent system to perform quantitative and clean transformations under ambient conditions.
A Bifunctional Copper Catalyst Enables Ester Reduction with H2: Expanding the Reactivity Space of Nucleophilic Copper Hydrides
Kaicharla, Trinadh,Ngoc, Trung Tran,Teichert, Johannes F.,Tzaras, Dimitrios-Ioannis,Zimmermann, Birte M.
supporting information, p. 16865 - 16873 (2021/10/20)
Employing a bifunctional catalyst based on a copper(I)/NHC complex and a guanidine organocatalyst, catalytic ester reductions to alcohols with H2 as terminal reducing agent are facilitated. The approach taken here enables the simultaneous activation of esters through hydrogen bonding and formation of nucleophilic copper(I) hydrides from H2, resulting in a catalytic hydride transfer to esters. The reduction step is further facilitated by a proton shuttle mediated by the guanidinium subunit. This bifunctional approach to ester reductions for the first time shifts the reactivity of generally considered "soft"copper(I) hydrides to previously unreactive "hard"ester electrophiles and paves the way for a replacement of stoichiometric reducing agents by a catalyst and H2.
