- Selective reduction of aromatic nitro compounds to aromatic amines by Baker's yeast in basic solution
-
Aromatic nitro compounds containing o-, m- or p-electron withdrawing groups, such as carbonyl, halogen and nitro, were selectively and rapidly reduced to their corresponding amino derivatives in good yields using Bakers' Yeast in basic solution.
- Baik, Woonphil,Han, Jeong Lim,Lee, Ki Chang,Lee, Nam Ho,Kini, Byeong Hyo,Hahn, Jung-Tai
-
-
Read Online
- Structural and Substituent Effect on (+.) vs. (+) Formation in Fast Atom Bombardment Mass Spectra of Simple Organic Compounds
-
The peak intensity ratios of (+.) vs. (+) were measured in the fast atom bombardment (FAB) mass spectra of readily available test compounds with 3-nitrobenzyl alcohol as the matrix.For simple aromatic amines, the ratio increases as the ionization energy of the substrate decreases. 4-Subsituted benzophenones showed preferential formation of (+) ions, regardless of the nature of the substituents.This is probably due to the fact that the benzophenones have carbonyl groups which can form hydrogen bonds with the matrix molecule.The peak intensity ratio is roughly proportional to the Hammett ?+.Among 4-substituted biphenyls, both bromo and chloro substituents afforded abnormally high peak intensity ratios.The effects of the substituents in these compounds are discussed semi-quantitatively in terms of the Hammett correlation and the hard and soft acids and bases principle.The mechanism of ion formation in FAB and chemical ionization (CI) ion sources appeared to be different because some of the compounds studied showed an intense (+.) peak with a relatively weak (+) peak in FAB spectra but exhibited a strong (+) peak in ordinary CI spectra.
- Nakata, Hisao,Tanaka, Katsunori
-
-
Read Online
- A new cobalt triangular prism supramolecular flask: Encapsulation of a quinhydrone cofactor for hydrogenation of nitroarenes with high selectivity and efficiency
-
A new M6L3 metal-organic triangular prism host Co–L1 was synthesized that contains a sufficiently large cavity for encapsulation of a quinhydrone (QHQ) electron transporter to form charge-transfer complexes for accelerating electron delivery. Through the strong coordinating ability of the ONP chelator, a suitable redox potential was obtained for the combination of light-driven proton reduction with the selective hydrogenation of nitro groups. The experimental results showed that the regulation of redox potential is very beneficial for hydrogen production and that the introduction of QHQ accelerates electron transfer and increases the reaction rate. Control experiments based on an inhibitor and a mononuclear compound resembling the cobalt corner of the triangular prism suggest enzyme-like behaviour. This synthetic platform, in which the supramolecular systems exhibit high activity and stability, provides an alternative strategy to selectively hydrogenate nitroarenes using light as a clean energy source.
- Zheng, Sijia,Zhao, Liang,Wei, Jianwei,He, Cheng,Liu, Guangzhou,Duan, Chunying
-
-
Read Online
- Xantphos-ligated palladium dithiolates: An unprecedented and convenient catalyst for the carbonylative Suzuki–Miyaura cross-coupling reaction with high turnover number and turnover frequency
-
Xantphos- and dithiolate-ligated macrocyclic palladium complexes as an efficient and stable catalyst for the carbonylative Suzuki–Miyaura cross-coupling reaction have been synthesized. The catalysts were characterized by 1H-nuclear magnetic resonance (NMR), CHNS (carbon, hydrogen, nitrogen, and sulfur) analysis, melting point analysis, and 31P-NMR spectroscopy. Several sensitive functional groups (e.g., –NO2, –F, –Cl, –Br, –NH2, and –CN) on the aromatic ring were well tolerated in the carbonylative Suzuki–Miyaura coupling reaction. The present palladium complexes produce six times higher turnover number (TON) and five times higher turnover frequency (TOF) compared with conventional homogeneous palladium precursors. Maximum TONs in the range of 105 to 106 and TOF in the range of 104 to 105 could be generated by a very low amount of catalyst loading (10–5?mol%).
- Gaikwad, Vinayak V.,Mane, Pravin A.,Dey, Sandip,Bhanage, Bhalchandra M.
-
-
Read Online
- Fe2O3/NGr@C- and Co-Co3O4/NGr@C-catalysed hydrogenation of nitroarenes under mild conditions
-
An improved hydrogenation of nitroarenes using nano-structured iron- and cobalt-based catalysts is presented. Modifications of the heterogeneous catalysts by N-doped graphene-flakes are crucial for the success of selective reductions. The use of polar solvents and basic additives has a significant positive influence on the rate of reduction of nitroarenes. This allows performing non-noble metal-catalysed hydrogenations under very mild reaction conditions (e.g. 70 °C and 20 bar). On the basis of the obtained catalytic results a heterolytic mechanism for the hydrogenation process is postulated, too.
- Formenti, Dario,Topf, Christoph,Junge, Kathrin,Ragaini, Fabio,Beller, Matthias
-
-
Read Online
- Silver-catalyzed decarboxylative acylation of arylglyoxylic acids with arylboronic acids
-
The silver-catalyzed coupling of arylboronic acids with arylglyoxylic acids was found to be an extremely efficient route for the synthesis of unsymmetrical diaryl ketones. It can be conducted on a gram scale under mild and open-flask conditions with good functional group compatibility, avoiding the addition of expensive and/or toxic metals. This journal is
- Cheng, Kai,Zhao, Baoli,Qi, Chenze
-
-
Read Online
- TITANIUM-MEDIATED REDUCTION OF NITROBENZENES AND BENZIL WITH DIALKYL TELLURIDE
-
In the presence of titanium(IV) chloride, nitrobenzenes are easily reduced with dialkyl telluride to give the corresponding amines in good to moderate yields.Benzil is reduced to benzoin which, on a further treatment, is converted to desoxybenzoin.
- Suzuki, Hitomi,Hanazaki, Yasuaki
-
-
Read Online
- A practical and chemoselective reduction of nitroarenes to anilines using activated iron
-
Reduction of nitroarenes to anilines using activated iron generated by Fe/HCl or Zn/FeSO4 is described. A variety of functional groups such as alkyne, ketone, enone, nitrile, lactone, and aromatic halide are well tolerated under these conditions.
- Liu, Yugang,Lu, Yansong,Prashad, Mahavir,Repic, Oljan,Blacklock, Thomas J.
-
-
Read Online
- Silica gel supported AlCl3 catalyzed Friedel-Crafts acylation of aromatic compounds
-
Silica gel supported aluminium trichloride (SiO2-AlCl3) has been shown to be a mild, efficient, and chemoselective heterogeneous Lewis acid catalyst for the acylation of aromatic compounds with acid chlorides. The catalyst can be reused up to five times after simple washing with ether and is stable (as a bench top catalyst).
- Boroujeni, Kaveh Parvanak
-
-
Read Online
- Continuous-flow synthesis of primary amines: Metal-free reduction of aliphatic and aromatic nitro derivatives with trichlorosilane
-
The metal-free reduction of nitro compounds to amines mediated by trichlorosilane was successfully performed for the first time under continuous-flow conditions. Aromatic as well as aliphatic nitro derivatives were converted to the corresponding primary amines in high yields and very short reaction times with no need for purification. The methodology was also extended to the synthesis of two synthetically relevant intermediates (precursors of baclofen and boscalid).
- Porta, Riccardo,Puglisi, Alessandra,Colombo, Giacomo,Rossi, Sergio,Benaglia, Maurizio
-
-
Read Online
- Synthesis of CoFe2O4@Pd/Activated carbon nanocomposite as a recoverable catalyst for the reduction of nitroarenes in water
-
Efficient reduction of nitro compounds into amines is an important industrial transformation. So, it is a great deal to design new catalysts for efficient reduction of the nitro compounds especially in water. In this work, a new magnetic Pd/activated carbon nanocomposite (CoFe2O4@Pd/AC) was synthesized via metal-impregnation-pyrolysis method. The CoFe2O4@Pd/AC was fully characterized by FT-IR, PXRD, FESEM, TEM, VSM, EDX-mapping and BET techniques. The results showed that CoFe2O4@Pd/AC is a highly reactive and easily recoverable magnetic catalyst for the reduction of the nitro compounds by using NaBH4 in water. For instance, aniline was obtained in high yield (99%) after 75 ?min at 25 ?C by using just 6 ?mg of the catalyst. In addition, CoFe2O4@Pd/AC was recovered by a simple magnetic decantation and it exhibits stable activity and remains intact during the catalytic process with no significant loss in activity (8 cycles).
- Hamadi, Hosein,Kazeminezhad, Iraj,Mohammadian, Sara
-
-
- Selective Oxidation of Alkylarenes to the Aromatic Ketones or Benzaldehydes with Water
-
Here a palladium-catalyzed oxidation method for converting alkylarenes into the aromatic ketones or benzaldehydes with water as the only oxygen donor is reported. This C-H bond oxidation functionalization does not require other oxidants and hydrogen accep
- Du, Jihong,Duan, Baogen,Liu, Kun,Liu, Renhua,Yu, Feifei,Yuan, Yongkun,Zhang, Chenyang,Zhang, Jin
-
supporting information
(2022/02/09)
-
- PhSe(O)OH/NHPI-catalyzed oxidative deoximation reaction using air as oxidant
-
A novel oxidative deoximation method was developed in this article. Compared with the reported organoselenium-catalyzed oxidative deoximation reaction, this reaction employed N-hydroxyphthalimide (NHPI) as the co-catalyst, so that the oxidative deoximation reaction could utilize air as oxidant in the green DMC solvent under mild reaction conditions. Control experiments and X-ray photoelectron spectroscopy (XPS) analysis results indicated that NHPI was essential for activating the catalytic organoselenium species. It could accelerate the activation of molecular oxygen in air to promote the reaction process. The reaction can avoid metal residues in product and is of potential application values in pharmaceutical industry due to the transition metal-free process.
- Shi, Yaocheng,Wang, Feng,Yang, Chenggen,Yu, Lei
-
-
- Deep eutectic solvents as H2-sources for Ru(II)-catalyzed transfer hydrogenation of carbonyl compounds under mild conditions
-
The employment of easily affordable ruthenium(II)-complexes as pre-catalysts in the transfer hydrogenation of carbonyl compounds in deep eutectic media is described for the first time. The eutectic mixture tetrabutylammonium bromide/formic acid = 1/1 (TBABr/HCOOH = 1/1) acts both as reaction medium and hydrogen source. The addition of a base is required for the process to occur. An extensive optimization of the reaction conditions has been carried out, in terms of catalyst loading, type of complexes, H2-donors, reaction temperature and time. The combination of the dimeric complex [RuCl(p-cymene)-μ-Cl]2 (0.01–0.05 eq.) and the ligand dppf (1,1′-ferrocenediyl-bis(diphenylphosphine)ferrocene) in 1/1 molar ratio has proven to be a suitable catalytic system for the reduction of several and diverse aldehydes and ketones to their corresponding alcohols under mild conditions (40–60 °C) in air, showing from moderate to excellent tolerability towards different functional groups (halogen, cyano, nitro, phenol). The reduction of imine compounds to their corresponding amine derivatives was also studied. In addition, the comparison between the results obtained in TBABr/HCOOH and in organic solvents suggests a non-innocent effect of the DES medium during the process.
- Cavallo, Marzia,Arnodo, Davide,Mannu, Alberto,Blangetti, Marco,Prandi, Cristina,Baratta, Walter,Baldino, Salvatore
-
supporting information
(2021/02/22)
-
- Method for reducing aromatic nitro into arylamine
-
The invention relates to a method for reducing aromatic nitro to arylamine. The method comprises the following steps: (1) taking an aromatic nitro compound as a raw material, water as a hydrogen source, a palladium compound, cheap and easy to obtain, as a catalyst and tetrahydroxydiboron as an additive to reduce nitro to obtain a product; (2) taking the aromatic nitro compound as the raw material, a copper salt, cheap and easy to obtain, as the catalyst, the tetrahydroxydiboron as the additive to reduce the nitro to obtain a product; and (3) taking the aromatic nitro compound as the raw material, water as the hydrogen source, and the tetrahydroxydiboron as the additive, without needing a metal catalyst, to reduce the nitro to obtain a product. A preparation method for the arylamine, which is provided by the invention, is mild in reaction condition, low in costs, environment-friendly, high in yield, and suitable for industrial production.
- -
-
Paragraph 0121-0124; 0221-0224; 0265-0268
(2020/07/15)
-
- A Bifunctional Iron Nanocomposite Catalyst for Efficient Oxidation of Alkenes to Ketones and 1,2-Diketones
-
We herein report the fabrication of a bifunctional iron nanocomposite catalyst, in which two catalytically active sites of Fe-Nx and Fe phosphate, as oxidation and Lewis acid sites, were simultaneously integrated into a hierarchical N,P-dual doped porous carbon. As a bifunctional catalyst, it exhibited high efficiency for direct oxidative cleavage of alkenes into ketones or their oxidation into 1,2-diketones with a broad substrate scope and high functional group tolerance using TBHP as the oxidant in water under mild reaction conditions. Furthermore, it could be easily recovered for successive recycling without appreciable loss of activity. Mechanistic studies disclose that the direct oxidation of alkenes proceeds via the formation of an epoxide as intermediate followed by either acid-catalyzed Meinwald rearrangement to give ketones with one carbon shorter or nucleophilic ring-opening to generate 1,2-diketones in a cascade manner. This study not only opens up a fancy pathway in the rational design of Fe-N-C catalysts but also offers a simple and efficient method for accessing industrially important ketones and 1,2-diketones from alkenes in a cost-effective and environmentally benign fashion.
- Ma, Zhiming,Ren, Peng,Song, Tao,Xiao, Jianliang,Yang, Yong,Yuan, Youzhu
-
p. 4617 - 4629
(2020/05/19)
-
- Carbonylative Suzuki coupling and alkoxycarbonylation of aryl halides using palladium supported on phosphorus-doped porous organic polymer as an active and robust catalyst
-
Developing highly active catalysts with the combined advantages of molecular and solid catalysis is considered as the “Holy Grail” in the area of catalysis research. Herein, a phosphorus-doped porous polymer-immobilized palladium was successfully developed as an efficient, robust, and recyclable catalyst for the carbonylative Suzuki coupling and alkoxycarbonylation reactions of aryl halides. Rather than just as an immobilizing molecular catalyst, palladium supported on phosphorus-doped porous organic polymer exhibits even better catalytic performances than that of its analogue homogeneous catalysts in both carbonylation reactions. Moreover, the catalyst can be easily separated and reused for at least 5 times without significant loss in reactivity. Importantly, the catalyst was highly stable under carbonylation reaction conditions, and no palladium nanoparticle was observed even after the 5th reuse.
- Wan, Yali,Song, Fangxiang,Ye, Tao,Li, Guangxing,Liu, Dingfu,Lei, Yizhu
-
-
- Starch functionalized creatine for stabilization of gold nanoparticles: Efficient heterogeneous catalyst for the reduction of nitroarenes
-
Selective reduction of nitroaromatic pollutants into amines with recoverable and reusable heterogeneous catalysts is highly desirable. Herein, we prepared and characterized an efficient novel catalyst comprising 4 nm size Au nanoparticles supported on creatine modified starch. Using this catalyst, efficient reduction of nitroarenes into amines at room temperature in aqueous media was achieved. The presence of creatine in the structure of the catalyst plays important role in amount of Au loading, efficiency of the catalyst, recycling times, and leaching of Au compared to starch supported Au without creatine.
- Gholinejad, Mohammad,Dasvarz, Neda,Shojafar, Mohammad,Sansano, José M.
-
-
- Superior activity and selectivity of heterogenized cobalt catalysts for hydrogenation of nitroarenes
-
The development of improved catalysts for highly selective hydrogenation of nitroarenes is described. For this purpose Co nanoparticles were supported on ordered mesoporous carbon CMK-3 and characterized in detail. The optimal CMK-3-CoPc catalyst exhibits excellent hydrogenation activity for several (hetero)aromatic nitro compounds and yielded the corresponding anilines under mild conditions (40 °C, 20 bar H2).
- Li, Wu,Artz, Jens,Broicher, Cornelia,Junge, Kathrin,Hartmann, Heinrich,Besmehn, Astrid,Palkovits, Regina,Beller, Matthias
-
p. 157 - 162
(2019/01/10)
-
- General and Chemoselective Copper Oxide Catalysts for Hydrogenation Reactions
-
Copper oxide catalysts have been prepared by pyrolysis of copper acetate on aluminum oxide. The material resulting from pyrolysis at 800 °C allows for catalytic hydrogenations at low temperature of a variety of unsaturated compounds such as quinolines, alkynes, ketones, imines, and polycyclic aromatic hydrocarbons as well as nitroarenes with good activity and selectivity.
- Li, Wu,Cui, Xinjiang,Junge, Kathrin,Surkus, Annette-Enrica,Kreyenschulte, Carsten,Bartling, Stephan,Beller, Matthias
-
p. 4302 - 4307
(2019/05/08)
-
- Polymer-incarcerated palladium-catalyzed facile: In situ carbonylation for the synthesis of aryl aldehydes and diaryl ketones using CO surrogates under ambient conditions
-
In this existing work, an efficient polymer-supported palladium catalyst, a furfurylamine-functionalized Merrifield complex of palladium [Pd@(Merf-FA)], was synthesized and characterized, showing excellent catalytic activity towards in situ carbonylation reactions using carbon monoxide surrogates like formic acid and chloroform. Herein, we examined the catalytic activity of the Pd@(Merf-FA) catalyst for the formylation of aryl iodides and carbonylative Suzuki-Miyaura coupling reactions. The Pd@(Merf-FA) catalyst was systematically characterized by several techniques like HRTEM, elemental mapping, PXRD, TGA-DTA, FESEM, UV-vis, EDAX, CHN and AAS analysis. The catalyst is highly recyclable, able to be recycled up to six times without showing any significant decrease in catalytic activity. The [Pd@(Merf-FA)] catalyst proved to be more efficient compared to the corresponding homogeneous palladium catalyst. In addition, the leaching experiment of the synthesized catalyst was studied, which showed that negligible leaching of metal occurred from the polymeric support.
- Dey, Tusar Kanto,Basu, Priyanka,Riyajuddin, Sk,Ghosh, Aniruddha,Ghosh, Kaushik,Manirul Islam, Sk
-
p. 9802 - 9814
(2019/07/04)
-
- A convenient and practical heterogeneous palladium-catalyzed carbonylative Suzuki coupling of aryl iodides with formic acid as carbon monoxide source
-
A practical heterogeneous palladium-catalyzed carbonylative Suzuki coupling of aryl iodides with arylboronic acids under carbon monoxide gas-free conditions has been developed using a bidentate phosphino-functionalized magnetic nanoparticle-immobilized palladium(II) complex as catalyst. Formic acid was utilized as the carbon monoxide source with dicyclohexylcarbodiimide as the activator, and a wide variety of biaryl ketones were generated in moderate to high yields. The new heterogeneous palladium catalyst can be prepared via a simple procedure and can easily be separated from a reaction mixture by simply applying an external magnet and recycled up to 10 times without any loss of activity.
- You, Shengyong,Yan, Chenyu,Zhang, Rongli,Cai, Mingzhong
-
-
- Metal-free deoxygenation and reductive disilylation of nitroarenes by organosilicon reducing reagents
-
A metal-free deoxygenation and reductive disilylation of nitroarenes was achieved using N,N’-bis(trime-thylsilyl)-4,4’-bipyridinylidene (1) under mild and neutral reaction conditions, and a broad functional group tolerance was possible in this reaction. Mono-deoxygenation, giving a synthetically valuable N,O-bis(trimethylsilyl)phe-nylhydroxylamine (7a) as a readily available and safe phenylnitrene source from nitrobenzene, and double-deoxy-genation, giving N,N-bis(trimethylsilyl)anilines 8, were easily controlled by varying the amounts of 1 and reaction temperature as well as adding dibenzothiophene (DBTP). Reaction of 2-arylnitrobenzenes with 1 resulted in the formation of the corresponding carbazoles 14 via in situ-gen-erated phenylnitrene species derived by thermolysis of N,O-bis(trimethylsilyl)phenylhydroxylamines 7, followed by their subsequent intramolecular C H insertion. In addition, the intramolecular N N coupling reaction proceeded in the reduction of 2,2’-dinitrobiphenyl derivatives by 1, giving the corresponding benzo[c]cinnolines.
- Bhattacharjee, Argha,Hosoya, Hiromu,Ikeda, Hideaki,Nishi, Kohei,Tsurugi, Hayato,Mashima, Kazushi
-
supporting information
p. 11278 - 11282
(2018/10/20)
-
- Cu-catalyzed reduction of azaarenes and nitroaromatics with diboronic acid as reductant
-
A ligand-free copper-catalyzed reduction of azaarenes with diboronic acid as reductant in an aprotic solvent under mild conditions has been developed. Most interestingly, the nitroazaarenes could be reduced exclusively to give the corresponding amines without touching the azaarene moieties. Furthermore, the reductive amination of aromatic nitro compounds and aromatic aldehydes has also been realized. A series of hydrogenated azaarenes and secondary amines were obtained with good functional group tolerance.
- Pi, Danwei,Zhou, Haifeng,Zhou, Yanmei,Liu, Qixing,He, Renke,Shen, Guanshuo,Uozumi, Yasuhiro
-
p. 2121 - 2129
(2018/03/23)
-
- Preparation and characterization of Fe3O4/SiO2/CdS nanocomposites as efficient magnetic photocatalysts for the reduction of nitro compounds under visible LED irradiation
-
A series of magnetic Fe3O4/SiO2/CdS nanocomposites were synthesized through a facile and convenient method. The characterization of the prepared nanocomposites was performed by Fourier transform infrared spectroscopy (FT-IR), X-ray diffraction (XRD), scanning electron microscopy (SEM), transmission electron microscopy (TEM), energy dispersive X-ray (EDX), vibrating sample magnetometer (VSM), UV–Vis spectroscopy, and UV–vis diffuse reflectance spectroscopy (DRS). The prepared magnetic photocatalysts were first utilized for the photocatalytic reduction of nitro compounds under visible LED irradiation. The Fe3O4/SiO2/CdS nanocomposites exhibited enhanced photoactivity compared with the bare CdS and commercial CdS (Aldrich). The results demonstrated that Fe3O4/SiO2/CdS nanocomposites have potential to provide a promising visible light driven photocatalyst for the selective reduction of nitro compounds to corresponding amines under mild conditions. The prepared photocatalyst can be recovered by magnetic separation and successfully reused for 3 cycles.
- Eskandari, Parvin,Kazemi, Foad
-
p. 233 - 239
(2018/06/15)
-
- NITROGEN-CONTAINING BIOPOLYMER-BASED CATALYSTS, THEIR PREPARATION AND USES IN HYDROGENATION PROCESSES, REDUCTIVE DEHALOGENATION AND OXIDATION
-
The present invention relates to a process for the preparation of a nitrogen containing biopolymer-based catalyst by pyrolysis of a metal complex with a nitrogen-containing biopolymer and to the nitrogen containing biopolymer-based catalysts obtainable by this process. In particular, the invention relates to a nitrogen containing biopolymer-based catalyst comprising metal particles and at least one nitrogen containing carbon layer. The invention also relates to the use of a nitrogen containing biopolymer-based catalyst in a hydrogenation process, preferably in a process for hydrogenation of nitroarenes, nitriles or imines; in a reductive dehalogenation process of C-X bonds, wherein X is CI, Br or I, preferably in a process for dehalogenation of organohalides or in a process for deuterium labelling of arenes via dehalogenation of organohalides; or in an oxidation process. Further, the invention relates to a metal complex with the nitrogen containing biopolymer, wherein the metal is a transition metal selected from the group consisting of manganese, ruthenium, cobalt, rhodium, nickel, palladium and platinum, preferably cobalt or nickel, and wherein the nitrogen containing biopolymer is selected from chitosan, chitin and a polyamino acid, preferably chitosan or chitin.
- -
-
Page/Page column 31-32; 34
(2018/07/29)
-
- Coumarin-surfactant modified polyoxometalate catalyzed cross dehydrogenative coupling of benzyl alcohol with the: Para -C-H of unprotected aniline
-
This paper presents a novel method for synthesizing para-aminobenzophenone and its derivatives (p-ABPs) using a coumarin-surfactant modified polyoxometalate as the catalyst. Preliminary mechanistic studies indicate that the reaction has undergone an oxidative cross dehydrogenative coupling process. This method has the advantages of an easy process, a convenient raw material source, safe and green oxidants, and tolerances of several functional groups.
- Xu, Qian,Yu, Gang,Liu, Min,Peng, Chang,Banks, M. Katherine,Xu, Weijian,Wu, Ruoxi,Lu, Yanbing
-
p. 5133 - 5136
(2018/10/24)
-
- STABILIZATION OF ACTIVE METAL CATALYSTS AT METAL-ORGANIC FRAMEWORK NODES FOR HIGHLY EFFICIENT ORGANIC TRANSFORMATIONS
-
Metal-organic framework (MOFs) compositions based on post?synthetic metalation of secondary building unit (SBU) terminal or bridging OH or OH2 groups with metal precursors or other post-synthetic manipulations are described. The MOFs provide a versatile family of recyclable and reusable single-site solid catalysts for catalyzing a variety of asymmetric organic transformations, including the regioselective boryiation and siiylation of benzyiic C—H bonds, the hydrogenation of aikenes, imines, carbonyls, nitroarenes, and heterocycles, hydroboration, hydrophosphination, and cyclization reactions. The solid catalysts can also be integrated into a flow reactor or a supercritical fluid reactor.
- -
-
Paragraph 0354-0356; 0359
(2019/01/07)
-
- Catalytic Reductions and Tandem Reactions of Nitro Compounds Using in Situ Prepared Nickel Boride Catalyst in Nanocellulose Solution
-
A mild and efficient method for the in situ reduction of a wide range of nitroarenes and aliphatic nitrocompounds to amines in excellent yields using nickel chloride/sodium borohydride in a solution of TEMPO-oxidized nanocellulose in water (0.01 wt %) is described. The nanocellulose has a stabilizing effect on the catalyst, which increases the turnover number and enables low loading of nickel catalyst (0.1-0.25 mol % NiCl2). In addition, two tandem protocols were developed in which the in situ formed amines were either Boc-protected to carbamates or further reacted with an epoxide to yield β-amino alcohols in excellent yields.
- Prathap, Kaniraj Jeya,Wu, Qiong,Olsson, Richard T.,Dinér, Peter
-
supporting information
p. 4746 - 4749
(2017/09/23)
-
- Hexafluoro-2-propanol-assisted quick and chemoselective nitro reduction using iron powder as catalyst under mild conditions
-
Hexafluoro-2-propanol as the promoter for the quick nitro reduction using a combination of iron powder and 2 N HCl aqueous solution is reported. This methodology has several positive features, as it is of room temperature, remarkably short reaction time. A wide range of substrates including those bearing reducible functional groups such as aldehyde, ketone, acid, ester, amide, nitrile, halogens, even allyl, propargyl and heterocycles are chemoselectively reduced in good to excellent yields, even on gram scale. Notably, the highly selective reduction of 3-nitrophenylboronic acid is achieved quantitatively. The reduction is also tolerant of common protecting groups, and aliphatic nitro compound, 1-nitrooctane can be reduced successfully.
- Chen, Xu-Ling,Ai, Bai-Ru,Dong, Yu,Zhang, Xiao-Mei,Wang, Ji-Yu
-
supporting information
p. 3646 - 3649
(2017/08/23)
-
- Preparation method for arylamine compounds
-
The invention relates to a preparation method for arylamine compounds, belonging to the fields of medical and chemical intermediate and related chemical technologies. The preparation method comprises the following steps: (1) adding nitro-substituted aromatic compounds, a nanometer porous metal catalyst and a solvent into a reaction vessel, introducing hydrogen and carrying out heating and stirring; and (2) after completion of reaction, subjecting a reaction solution obtained in the step (1) to pressure reduction so as to remove the solvent and carrying out column chromatography so as to obtain target products, i.e., the arylamine compounds. Compared with the prior art, the invention has the following advantages: the nanometer porous palladium catalyst used in the method can perform its unique catalytic activity under mild conditions, is convenient to recycle as a catalyst and can be repeatedly used after simple filtering and cleaning; and the catalyst has stable structure and high catalytic activity and is not obviously reduced in catalytic activity after repeated usage, so industrialization of the arylamine compounds is made possible.
- -
-
Paragraph 0058-0059
(2017/09/26)
-
- Water as a hydrogen source in palladium-catalyzed reduction and reductive amination of nitroarenes mediated by diboronic acid
-
An unprecedented palladium-catalyzed chemoselective reduction and reductive amination of nitroarenes with water as a hydrogen source mediated by diboronic acid have been discovered. A series of aryl amines containing various reducible functional groups were obtained in good to excellent yields.
- Zhou, Yanmei,Zhou, Haifeng,Liu, Sensheng,Pi, Danwei,Shen, Guanshuo
-
p. 3898 - 3904
(2017/06/13)
-
- Single-Site Cobalt Catalysts at New Zr12(μ3-O)8(μ3-OH)8(μ2-OH)6 Metal-Organic Framework Nodes for Highly Active Hydrogenation of Nitroarenes, Nitriles, and Isocyanides
-
We report here the synthesis of a robust and porous metal-organic framework (MOF), Zr12-TPDC, constructed from triphenyldicarboxylic acid (H2TPDC) and an unprecedented Zr12 secondary building unit (SBU): Zr12(μ3-O)8(μ3-OH)8(μ2-OH)6. The Zr12-SBU can be viewed as an inorganic node dimerized from two commonly observed Zr6 clusters via six μ2-OH groups. The metalation of Zr12-TPDC SBUs with CoCl2 followed by treatment with NaBEt3H afforded a highly active and reusable solid Zr12-TPDC-Co catalyst for the hydrogenation of nitroarenes, nitriles, and isocyanides to corresponding amines with excellent activity and selectivity. This work highlights the opportunity in designing novel MOF-supported single-site solid catalysts by tuning the electronic and steric properties of the SBUs.
- Ji, Pengfei,Manna, Kuntal,Lin, Zekai,Feng, Xuanyu,Urban, Ania,Song, Yang,Lin, Wenbin
-
p. 7004 - 7011
(2017/05/31)
-
- Biomass-Derived Catalysts for Selective Hydrogenation of Nitroarenes
-
Development of catalytically active materials from biowaste represents an important aspect of sustainable chemical research. Three heterogeneous materials were synthesized from inexpensive biomass-based chitosan and abundant Co(OAc)2 using complexation followed by pyrolysis at various temperatures. These materials were applied in the catalytic hydrogenation of nitroarenes using molecular hydrogen. A variety of diversely functionalized nitroarenes including some pharmaceutically active compounds were converted into aromatic amines in high yields, with high selectivity, and with excellent functional group tolerance. This green protocol has also been implemented for the synthesis of a biologically important TRPC3 inhibitor.
- Sahoo, Basudev,Formenti, Dario,Topf, Christoph,Bachmann, Stephan,Scalone, Michelangelo,Junge, Kathrin,Beller, Matthias
-
p. 3035 - 3039
(2017/08/18)
-
- Carbonylative Suzuki cross-coupling reaction catalyzed by bimetallic Pd-Pt nanodendrites under ambient CO pressure
-
Pd-catalyzed reactions between aryl boronic acids and aryl halides have undergone rapid development since the pioneering work of Suzuki and co-workers in 1979. In this paper, we described a high-efficient and cost-effective bimetallic Pd-Pt nanodendrites catalyst based on a ligand-free strategy to synthesize diaryl ketones via CO direct insertion to boronic acids and aryl halides. A variety of aryl boronic acids and aryl halides were investigated, which showed great functional group tolerance and versatile aryl ketone products in high yield.
- Wang, Zheng-Jun,Wang, Xue-Yan,Wang, Xia,Liang, Zhi-Wu,Xu, Xinhua
-
-
- Base free Suzuki acylation reactions of sodium (aryl trihydroxyborate) salts: A novel synthesis of substituted aryl ketones
-
The first simple and efficient base free Pd(PPh3)4 catalysed synthesis of substituted aryl ketones from acyl chlorides and easily accessible sodium aryl trihydroxyborate salts in aqueous toluene is reported. The reaction conditions appeared versatile and tolerable to a variety of functional groups including, CF3, OMe, SMe, Br, NO2, F, OH and NH2 furnishing 25 examples of substituted aryl ketones in isolated yields of up to 96% in 24 h. Beside the high purity, the ease and convenience of the isolation compared to boronic acids, sodium aryl trihydroxyborate salts could be used subsequently without the addition of excess amount of an activator and are more user-friendly in terms of the use of accurate reaction stoichiometry.
- Sithebe, Siphamandla,Molefe, Patience
-
p. 305 - 311
(2017/07/13)
-
- A highly efficient heterogeneous copper-catalysed cascade reaction of aryl iodides with acetamidine hydrochloride leading to primary arylamines
-
A highly efficient heterogeneous copper-catalysed cascade reaction of aryl iodides with acetamidine hydrochloride was achieved in DMF in the presence of 10 mol% of an MCM-41-immobilised L-proline-copper(I) complex (MCM-41-L-proline-CuI) with Cs2CO3 as base, yielding a variety of primary arylamines in good to excellent yields. The new heterogeneous copper complex can be easily prepared from commercially readily available and inexpensive reagents, recovered by a simple filtration of the reaction solution and used at least seven more times without any decrease in activity.
- Huang, Xue,Xiao, Ruian,You, Chongren,Yan, Tao,Cai, Mingzhong
-
p. 315 - 320
(2017/06/19)
-
- Highly chemoselective reduction of azides to amines by Fe(0) nanoparticles in water at room temperature
-
A highly chemoselective reduction of aryl, heteroaryl, acyl and sulfonyl azides to the corresponding amines has been achieved by Fe(0) nanoparticles in water at room temperature in the absence of external hydride source. Several readily reducible functionalities including alkene, alkyne, S-S linkage, OTBDMS remain unaffected during reduction.
- Panja, Subir,kundu, Debasish,Ahammed, Sabir,Ranu, Brindaban C.
-
supporting information
p. 3457 - 3460
(2017/08/10)
-
- Chemoselective generation of acyl phosphates, acylium ion equivalents, from carboxylic acids and an organophosphate ester in the presence of a Br?nsted acid
-
We describe the chemoselective conversion of carboxylic acids to functional aromatic ketones promoted by a tailored organophosphate ester in the presence of a Br?nsted acid. The protonated phosphate ester reacts with the carboxylic acid to form acyl phosphate, which reacts with benzenes to give aromatic ketones, probably through the acylium ion or its equivalent. The reaction time is short even at room temperature, and the reaction is compatible with various other functional groups, including amines, olefins, esters, amides and nitriles.
- Sumita, Akinari,Otani, Yuko,Ohwada, Tomohiko
-
supporting information
p. 1482 - 1485
(2017/02/05)
-
- KCC-1 supported palladium nanoparticles as an efficient and sustainable nanocatalyst for carbonylative Suzuki-Miyaura cross-coupling
-
This work reports a cost-effective and sustainable protocol for the carbonylative Suzuki-Miyaura cross-coupling reaction catalyzed by palladium nanoparticles (Pd NPs) supported on fibrous nanosilica (KCC-1). Under mild reaction conditions, the KCC-1-PEI/Pd catalytic system showed a turnover number (TON) 28-times and a turnover frequency (TOF) 51-times higher than the best supported Pd catalyst reported in the literature for the carbonylative cross-coupling between 4-iodoanisole and phenylboronic acid, as a test reaction. Also, the catalyst could be recycled up to ten times with a marginal loss in activity after the eighth cycle. The high activity of the catalyst can be attributed to the fibrous nature of the KCC-1 support and PEI functionalization provided the enhanced stability.
- Gautam, Prashant,Dhiman, Mahak,Polshettiwar, Vivek,Bhanage, Bhalchandra M.
-
supporting information
p. 5890 - 5899
(2016/11/06)
-
- Synthetic method for ketoprofen drug intermediate p-aminobenzophenone
-
The invention discloses a synthetic method for a ketoprofen drug intermediate, i.e., p-aminobenzophenone. The method comprises the following steps: adding p-nitrobenzophenone into a hydrazinobenzene hydrochloride solution; carrying out heating for a reaction; then adding a 5-aminotetrazole solution drop by drop; carrying out pressure-reduced distillation after a reaction; then carrying out cooling, filtering and washing with a saline solution; adding a product of the previous step into an oxalic acid solution; carrying out heating for a reaction and then carrying out filtering; adding a filtrate obtained in the previous step into a oxalic acid solution; allowing a solid to be precipitated; and carrying out cooling, filtering, washing and dehydration with a dehydrating agent so as to obtain p-aminobenzophenone. According to the synthetic method provided by the invention, reaction time can be controlled to be 15 h or less and reaction yield can reach 90% or more. Compared with synthetic methods in the prior art, the synthetic method provided by the invention is greatly shortened in reaction time and greatly improved in yield; and the synthetic method provides a novel synthetic route and lays good foundation for further improvement of reaction yield.
- -
-
Paragraph 0017; 0018; 0023-0027; 0062-0065
(2017/06/14)
-
- Safe and Selective Nitro Group Reductions Catalyzed by Sustainable and Recyclable Fe/ppm Pd Nanoparticles in Water at Room Temperature
-
As a result of a unique synergy between ligand-free Fe/ppm Pd nanoparticles and PEG-containing designer surfactants, a facile and selective reduction of nitro-containing aromatics and heteroaromatics can be effected in water at room temperature in the presence of NaBH4. This new nanotechnology involves low catalyst loadings, is highly chemoselective, and tolerates a wide variety of functional groups. The process, which includes recycling of the entire aqueous medium, offers a general, environmentally responsible, and notably safe approach to highly valued reductions of nitro-containing compounds.
- Feng, Jie,Handa, Sachin,Gallou, Fabrice,Lipshutz, Bruce H.
-
supporting information
p. 8979 - 8983
(2016/07/26)
-
- Photocatalytic reduction of nitro aromatic compounds to amines using a nanosized highly active CdS photocatalyst under sunlight and blue LED irradiation
-
A variety of aromatic nitro compounds were chemoselectively reduced to the corresponding anilines using conveniently prepared nanosized CdS as a photocatalyst under the sunlight and blue LED irradiation. The results demonstrated that synthesized CdS nanostructures have the potential to provide a promising visible light driven photocatalyst for chemoselective reduction of nitro aromatics in the presence of nitrile and carbonyl groups to the corresponding amines under both sunlight and blue LED irradiation. Photoreduction of nitro aromatics by the prepared nanosized CdS with high surface area was faster than when using the commercially available CdS under both sunlight and LED irradiation. Nanosized CdS photocatalyst was prepared by a simple method without any capping agent. X-ray diffraction (XRD), energy dispersive spectrometry (EDAX), transmission electron microscopy (TEM), scanning electron microscopy (SEM), N2 absorption-desorption, diffuse reflectance spectroscopy (DRS), and flat band potential methods were employed for the characterization, which revealed that the prepared CdS nanoparticles have a well-resolved cubic structure with the size of around 10-30 nm and a band gap of 2.37 eV.
- Asghar Safari, Ali,Kazemi, Foad
-
p. 531 - 537
(2016/03/08)
-
- Carbonylative coupling of aryl tosylates/triflates with arylboronic acids under CO atmosphere
-
The carbonylative Suzuki-Miyaura reaction between aryl tosylates/triflates with arylboronic acid is herein reported, using base-free conditions and a balloon pressure of carbon monoxide. Under these conditions, unsymmetrical biaryl ketones were obtained in modest to excellent yields. This method was adapted to the synthesis of oxybenzone and ketoprofen in good yields under mild conditions.
- Hao, Cheng Yi,Wang, Dan,Li, Ya Wei,Dong, Lin Lin,Jin, Ying,Zhang, Xiu Rong,Zhu, He Yun,Chang, Sheng
-
p. 86502 - 86509
(2016/09/23)
-
- Efficient Friedel–Crafts benzoylation of aniline derivatives with 4-fluorobenzoyl chloride using copper triflate in the synthesis of aminobenzophenones
-
ABSTRACT: An efficient pathway for the synthesis of the aminobenzophenone derivatives via Friedel–Crafts benzoylation using copper triflate as catalyst is proposed. New derivatives are synthesized. The copper triflate could be easily recovered and reused without loss of catalytic activity. Both the use of ionic liquids and microwave heating turned out to be fruitful.
- Tran, Phuong Hoang,Phung, Huy Quang,Hansen, Poul Erik,Tran, Hai Ngoc,Le, Thach Ngoc
-
p. 893 - 901
(2016/07/06)
-
- Amination-Oxidation Strategy for the Copper-Catalyzed Synthesis of Monoarylamines
-
A novel approach for the synthesis of monoarylamines from aryl halides is presented. This method employs an inexpensive, nontoxic metal source (copper) and incorporates a stable ammonia surrogate (α-amino acids), obviating the need for special experimental setup or handling of ammonia reagents. This process, which is proposed to proceed via an amination-oxidation sequence, selectively promotes the transformation of a range of aryl and heteroaryl iodides as well as bromides to the corresponding monoarylamines.
- Thomas, Christopher,Wu, Marvin,Billingsley, Kelvin L.
-
p. 330 - 335
(2016/01/15)
-
- Palladacycle-Catalyzed Carbonylative Suzuki-Miyaura Coupling with High Turnover Number and Turnover Frequency
-
This work reports the carbonylative Suzuki-Miyaura coupling of aryl iodides catalyzed by palladacycles. More importantly, the palladacycles have been used to generate high turnover numbers (TON's) and turnover frequencies (TOF's). A range of aryl iodides can be coupled with arylboronic acids, generating TON's in the range of 106 to 107 and TOF's in the range of 105 to 106 h-1. Comparison of the palladacycles with a conventional palladium source shows their superiority in generating high TON's and TOF's.
- Gautam, Prashant,Bhanage, Bhalchandra M.
-
p. 7810 - 7815
(2015/08/18)
-
- Metal-Free Reduction of Aromatic and Aliphatic Nitro Compounds to Amines: A HSiCl3-Mediated Reaction of Wide General Applicability
-
A new, mild, metal-free, HSiCl3-mediated reduction of both aromatic and aliphatic nitro groups to amines that is of wide general applicability, tolerant of many functional groups, and respectful of the stereochemical integrity of stereocenters is reported.
- Orlandi,Tosi,Bonsignore,Benaglia
-
supporting information
p. 3941 - 3943
(2015/09/01)
-
- METHOD FOR PRODUCING HYDROGEN OR HEAVY HYDROGENS, METHOD FOR PRODUCING HYDROGENATED (PROTIATED, DEUTERATED OR TRITIATED) ORGANIC COMPOUND, METHOD FOR HYDROGENATING (PROTIATING, DEUTERATING OR TRITIATING) ORGANIC COMPOUND, METHOD FOR DEHALOGENATING ORGANIC COMPOUND HAVING HALOGEN, AND BALL FOR USE IN MECHANOCHEMICAL REACTION
-
Objects are to provide efficient methods for producing hydrogen or heavy hydrogens and for hydrogenating (protiating, deuterating or tritiating) an organic compound, and to provide an equipment and the like used therefor. A method for producing hydrogen or heavy hydrogens, containing subjecting water or heavy water to mechanochemical reaction in the presence of a catalyst metal, in which an energy density of a rotational acceleration of 75 G or more is applied to water or heavy water for 25 minutes or more, a method for producing a hydrogenated (protiated, deuterated or tritiated) organic compound, a method for hydrogenating (protiating, deuterating or tritiating) an organic compound, a method for dehalogenating an organic compound having halogen, and a ball for mechanochemical reaction are provided.
- -
-
Paragraph 0112
(2015/02/18)
-
- A Convenient Palladium-Catalyzed Carbonylative Suzuki Coupling of Aryl Halides with Formic Acid as the Carbon Monoxide Source
-
A practical palladium-catalyzed carbonylative Suzuki coupling of aryl halides under carbon monoxide gas-free conditions has been developed. Here, formic acid was utilized as the carbon monoxide source for the first time with acetic anhydride as the additive. A variety of diarylketones were produced in moderate to excellent yields from the corresponding aryl halides and arylboronic acids.
- Qi, Xinxin,Jiang, Li-Bing,Li, Hao-Peng,Wu, Xiao-Feng
-
supporting information
p. 17650 - 17656
(2015/12/05)
-
- Room-Temperature Decarboxylative Couplings of α-Oxocarboxylates with Aryl Halides by Merging Photoredox with Palladium Catalysis
-
Enabled by merging iridium photoredox catalysis and palladium catalysis, α-oxocarboxylate salts can be decarboxylatively coupled with aryl halides to generate aromatic ketones and amides at room temperature. DFT calculations suggest that this reaction proceeds through a Pd0-PdII-PdIII pathway, in which the PdIII intermediate is responsible for reoxidizing IrII to complete the IrIII-IrIII-IrII photoredox cycle. Like a mergin': Enabled by merging iridium photoredox catalysis and palladium catalysis, palladium-catalyzed decarboxylative coupling of α-oxocarboxylates with aryl halides can proceed at room temperature. DFT calculations suggest that a Pd0-PdII-PdIII catalytic cycle is merged with an IrIII-IrIII-IrII photoredox cycle, in which PdIII is responsible for oxidizing IrII to complete the photoredox cycle.
- Cheng, Wan-Min,Shang, Rui,Yu, Hai-Zhu,Fu, Yao
-
supporting information
p. 13191 - 13195
(2015/09/15)
-
- Pyrrolic nitrogen-doped carbon nanotubes: Physicochemical properties, interactions with Pd and their role in the selective hydrogenation of nitrobenzophenone
-
Nitrogen-doped carbon nanotubes (N-CNTs) containing 63%, 73% and 80% pyrrolic-N were synthesized and used to evaluate the influence of pyrrolic nitrogen on the physicochemical properties and catalytic activity of Pd supported on N-CNTs (Pd/N-CNTs). Micrographs of Pd/N-CNTs showed that Pd was located along the defect sites of N-CNTs indicating strong Pd-support interactions. X-ray photoelectron spectroscopy revealed that the abundance of Pd0 decreased while that of Pd2+ increased as the quantity of pyrrolic nitrogen increased. The Pd2+ species were formed as Pd-N coordination complexes, which stabilized Pd2+ nanoparticles. Selective hydrogenation of nitrobenzophenone to aminobenzophenone or p-benzylaniline was used to evaluate the catalytic performance of catalysts. Pd/N-CNTs exhibited a higher selectivity towards aminobenzophenone than Pd on carbon nanotubes and Pd on activated carbon. The enhanced selectivity towards nitro-reduction alone, observed with Pd/N-CNTs was attributed to the promoting effect of pyrrolic-N. Hence, Pd/N-CNTs are promising catalysts for the selective reduction of nitro arenes.
- Ombaka, Lucy M.,Ndungu, Patrick G.,Nyamori, Vincent O.
-
p. 109 - 122
(2015/02/19)
-
- Nickel-catalyzed amination of Aryl chlorides with ammonia or ammonium salts
-
The nickel-catalyzed amination of aryl chlorides to form primary arylamines occurs with ammonia or ammonium sulfate and a well-defined single-component nickel(0) precatalyst containing a Josiphos ligand and an η2-bound benzonitrile ligand. This system also catalyzes the coupling of aryl chlorides with gaseous amines in the form of their hydrochloride salts. Simple alternative: The title reaction, which results in primary arylamines, is catalyzed by well-defined single-component nickel(0) precatalysts containing a Josiphos ligand and an η2-bound benzonitrile ligand. This system also catalyzes the coupling of aryl chlorides with gaseous amines in the form of their hydrochloride salts.
- Green, Rebecca A.,Hartwig, John F.
-
supporting information
p. 3768 - 3772
(2015/03/18)
-
- Palladium catalyzed addition of arylboronic acid or indole to nitriles: Synthesis of aryl ketones
-
Aryl ketones can be synthesized conveniently by a palladium catalyzed addition of arylboronic acid to nitriles in aqueous triflic acid. This catalytic system was extended to the addition of unprotected indoles to nitriles under a slightly modified condition to produce 3-acyl indoles in good yields.
- Das, Tuluma,Chakraborty, Amarnath,Sarkar, Amitabha
-
supporting information
p. 7198 - 7202
(2015/01/09)
-
- Chemoselective reductions of nitroaromatics in water at room temperature
-
A robust and green protocol for the reduction of functionalized nitroarenes to the corresponding primary amines has been developed. It relies on inexpensive zinc dust in water containing nanomicelles derived from the commercially available designer surfactant TPGS-750-M. This mild process takes place at room temperature and tolerates a wide range of functionalities. Highly selective reductions can also be achieved in the presence of common protecting groups.
- Kelly, Sean M.,Lipshutz, Bruce H.
-
supporting information
p. 98 - 101
(2014/01/23)
-
