7228-47-9Relevant articles and documents
Pincerlike molybdenum complex and preparation method thereof, catalytic composition and application thereof, and alcohol preparation method
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Paragraph 0125-0130, (2021/08/11)
The invention discloses a clamp-type molybdenum complex, a preparation method, a corresponding catalyst composition and application. The method comprises the steps: obtaining 9 molybdenum complexes with different structures through coordination reaction of 2-(substituent ethyl)-(5, 6, 7, 8-tetrahydroquinolyl) amine and a corresponding carbonyl molybdenum metal precursor; and catalyzing a ketone compound transfer hydrogenation reaction through a molybdenum complex to generate 40 alcohol compounds. The preparation method of the molybdenum complex is simple, high in yield and good in stability. For a transfer hydrogenation reaction of ketone, the molybdenum-based catalytic system has high catalytic activity and small molybdenum loading capacity, is used for production of aromatic and aliphatic alcohols, and has the advantages of simple method, small environmental pollution and high yield.
Air Stable Iridium Catalysts for Direct Reductive Amination of Ketones
Polishchuk, Iuliia,Sklyaruk, Jan,Lebedev, Yury,Rueping, Magnus
supporting information, p. 5919 - 5922 (2021/03/08)
Half-sandwich iridium complexes bearing bidentate urea-phosphorus ligands were found to catalyze the direct reductive amination of aromatic and aliphatic ketones under mild conditions at 0.5 mol % loading with high selectivity towards primary amines. One of the complexes was found to be active in both the Leuckart–Wallach (NH4CO2H) type reaction as well as in the hydrogenative (H2/NH4AcO) reductive amination. The protocol with ammonium formate does not require an inert atmosphere, dry solvents, as well as additives and in contrast to previous reports takes place in hexafluoroisopropanol (HFIP) instead of methanol. Applying NH4CO2D or D2 resulted in a high degree of deuterium incorporation into the primary amine α-position.
Direct reductive amination of ketones with ammonium salt catalysed by Cp*Ir(iii) complexes bearing an amidato ligand
Dai, Zengjin,Pan, Ying-Min,Wang, Shou-Guo,Yin, Qin,Zhang, Xumu
supporting information, p. 8934 - 8939 (2021/11/04)
A series of half-sandwich Ir(iii) complexes1-6bearing an amidato bidentate ligand were conveniently synthesized and applied to the catalytic Leuckart-Wallach reaction to produce racemic α-chiral primary amines. With 0.1 mol% of complex1, a broad range of ketones, including aryl ketones, dialkyl ketones, cyclic ketones, α-keto acids, α-keto esters and diketones, could be transformed to their corresponding primary amines with moderate to excellent yields (40%-95%). Asymmetric transformation was also attempted with chiral Ir complexes3-6, and 16% ee of the desired primary amine was obtained. Despite the unsatisfactory enantio-control achieved so far, the current exploration might stimulate more efforts towards the discovery of better chiral catalysts for this challenging but important transformation.
Iron-Catalyzed Wacker-type Oxidation of Olefins at Room Temperature with 1,3-Diketones or Neocuproine as Ligands**
Kataeva, Olga,Kn?lker, Hans-Joachim,Linke, Philipp,Puls, Florian
supporting information, p. 14083 - 14090 (2021/05/24)
Herein, we describe a convenient and general method for the oxidation of olefins to ketones using either tris(dibenzoylmethanato)iron(III) [Fe(dbm)3] or a combination of iron(II) chloride and neocuproine (2,9-dimethyl-1,10-phenanthroline) as catalysts and phenylsilane (PhSiH3) as additive. All reactions proceed efficiently at room temperature using air as sole oxidant. This transformation has been applied to a variety of substrates, is operationally simple, proceeds under mild reaction conditions, and shows a high functional-group tolerance. The ketones are formed smoothly in up to 97 % yield and with 100 % regioselectivity, while the corresponding alcohols were observed as by-products. Labeling experiments showed that an incorporated hydrogen atom originates from the phenylsilane. The oxygen atom of the ketone as well as of the alcohol derives from the ambient atmosphere.
Mechanistic Studies on the Hexadecafluorophthalocyanine–Iron-Catalyzed Wacker-Type Oxidation of Olefins to Ketones**
Grinenko, Vadim,Klau?, Hans-Henning,Kn?lker, Hans-Joachim,Puls, Florian,Seewald, Felix
, p. 16776 - 16787 (2021/11/04)
The hexadecafluorophthalocyanine–iron complex FePcF16 was recently shown to convert olefins into ketones in the presence of stoichiometric amounts of triethylsilane in ethanol at room temperature under an oxygen atmosphere. Herein, we describe an extensive mechanistic investigation for the conversion of 2-vinylnaphthalene into 2-acetylnaphthalene as model reaction. A variety of studies including deuterium- and 18O2-labeling experiments, ESI-MS, and 57Fe M?ssbauer spectroscopy were performed to identify the intermediates involved in the catalytic cycle of the oxidation process. Finally, a detailed and well-supported reaction mechanism for the FePcF16-catalyzed Wacker-type oxidation is proposed.
Amino Acid-Functionalized Metal-Organic Frameworks for Asymmetric Base–Metal Catalysis
Newar, Rajashree,Akhtar, Naved,Antil, Neha,Kumar, Ajay,Shukla, Sakshi,Begum, Wahida,Manna, Kuntal
supporting information, p. 10964 - 10970 (2021/03/29)
We report a strategy to develop heterogeneous single-site enantioselective catalysts based on naturally occurring amino acids and earth-abundant metals for eco-friendly asymmetric catalysis. The grafting of amino acids within the pores of a metal-organic framework (MOF), followed by post-synthetic metalation with iron precursor, affords highly active and enantioselective (>99 % ee for 10 examples) catalysts for hydrosilylation and hydroboration of carbonyl compounds. Impressively, the MOF-Fe catalyst displayed high turnover numbers of up to 10 000 and was recycled and reused more than 15 times without diminishing the enantioselectivity. MOF-Fe displayed much higher activity and enantioselectivity than its homogeneous control catalyst, likely due to the formation of robust single-site catalyst in the MOF through site-isolation.
Well-defined Cp*Co(III)-catalyzed Hydrogenation of Carbonates and Polycarbonates
Dahiya, Pardeep,Gangwar, Manoj Kumar,Sundararaju, Basker
, p. 934 - 939 (2020/12/15)
We herein report the catalytic hydrogenation of carbonates and polycarbonates into their corresponding diols/alcohols using well-defined, air-stable, high-valent cobalt complexes. Several novel Cp*Co(III) complexes bearing N,O-chelation were isolated for the first time and structurally characterized by various spectroscopic techniques including single crystal X-ray crystallography. These novel Co(III) complexes have shown excellent catalytic activity to produce value added diols/alcohols from carbonate and polycarbonates through hydrogenation using molecular hydrogen as sole reductant or iPrOH as transfer hydrogenation source. To demonstrate the developed methodology's practical applicability, we have recycled the bisphenol A monomer from compact disc (CD) through hydrogenation under the established reaction conditions using phosphine-free, earth-abundant, air- and moisture-stable high-valent cobalt catalysts.
Synthesis and catalytic activity of N-heterocyclic silylene (NHSi) iron (II) hydride for hydrosilylation of aldehydes and ketones
Du, Xinyu,Qi, Xinghao,Li, Kai,Li, Xiaoyan,Sun, Hongjian,Fuhr, Olaf,Fenske, Dieter
, (2021/05/29)
A novel silylene supported iron hydride [Si, C]FeH (PMe3)3 (1) was synthesized by C (sp3)-H bond activation with zero-valent iron complex Fe (PMe3)4. Complex 1 was fully characterized by spectroscopic methods and single crystal X-ray diffraction analysis. To the best of our knowledge, 1 is the first example of silylene-based hydrido chelate iron complex produced through activation of the C (sp3)?H bond. It was found that complex 1 exhibited excellent catalytic activity for hydrosilylation of aldehydes and ketones. The catalytic system showed good tolerance and catalytic activity for the substrates with different functional groups on the benzene ring. It is worth mentioning that, the experimental results showed that both ketones and aldehydes could be reduced in good to excellent yields under the same catalytic conditions. Based on the experiments and literature reports, a possible catalytic mechanism was proposed.
Nickel-Mediated Enantiospecific Silylation via Benzylic C-OMe Bond Cleavage
Balakrishnan, Venkadesh,Murugesan, Vetrivelan,Chindan, Bincy,Rasappan, Ramesh
supporting information, p. 1333 - 1338 (2021/02/20)
Benzylic stereocenters are found in bioactive and drug molecules, as enantiopure benzylic alcohols have been used to build such a stereogenic center, but are limited to the construction of a C-C bond. Silylation of alkyl alcohols has the potential to build bioactive molecules and building blocks; however, the development of such a process is challenging and unknown. Herein, we describe an unprecedented AgF-assisted nickel catalysis in the enantiospecific silylation of benzylic ethers.
MATERIALS COMPRISING CARBON-EMBEDDED COBALT NANOPARTICLES, PROCESSES FOR THEIR MANUFACTURE, AND USE AS HETEROGENEOUS CATALYSTS
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Page/Page column 17; 18, (2021/03/13)
The present invention relates to catalytically active material, comprising grains of non-graphitizing carbon with cobalt nanoparticles dispersed therein, wherein dP, the average diameter of cobalt nanoparticles in the non-graphitizing carbon grains, is in the range of 1 nm to 20 nm, D, the average distance between cobalt nanoparticles in the non-graphitizing carbon grains, is in the range of 2 nm to 150 nm, and ω, the combined total mass fraction of metal in the non-graphitizing carbon grains, is in the range of 30 wt% to 70 wt% of the total mass of the non-graphitizing carbon grains, and wherein dP, D and ω conform to the following relation: 4.5 dP / ω > D ≥ 0.25 dP / ω. The present invention, further, relates to a process for the manufacture of material according to the invention, as well as its use as a catalyst.
