5617-41-4Relevant articles and documents
Stainless Steel-Mediated Hydrogen Generation from Alkanes and Diethyl Ether and Its Application for Arene Reduction
Sawama, Yoshinari,Yasukawa, Naoki,Ban, Kazuho,Goto, Ryota,Niikawa, Miki,Monguchi, Yasunari,Itoh, Miki,Sajiki, Hironao
supporting information, p. 2892 - 2896 (2018/05/29)
Hydrogen gas can be generated from simple alkanes (e.g., n-pentane, n-hexane, etc.) and diethyl ether (Et2O) by mechanochemical energy using a planetary ball mill (SUS304, Fritsch Pulverisette 7), and the use of stainless steel balls and vessel is an important factor to generate the hydrogen. The reduction of organic compounds was also accomplished using the in-situ-generated hydrogen. While the use of pentane as the hydrogen source facilitated the reduction of the olefin moieties, the arene reduction could proceed using Et2O. Within the components (Fe, Cr, Ni, etc.) of the stainless steel, Cr was the metal factor for the hydrogen generation from the alkanes and Et2O, and Ni metal played the role of the hydrogenation catalyst.
Upgrading of aromatic compounds in bio-oil over ultrathin graphene encapsulated Ru nanoparticles
Shi, Juanjuan,Zhao, Mengsi,Wang, Yingyu,Fu, Jie,Lu, Xiuyang,Hou, Zhaoyin
supporting information, p. 5842 - 5848 (2016/05/24)
Fast pyrolysis of biomass for bio-oil production is a direct route to renewable liquid fuels, but raw bio-oil must be upgraded in order to remove easily polymerized compounds (such as phenols and furfurals). Herein, a synthesis strategy for graphene encapsulated Ru nanoparticles (NPs) on carbon sheets (denoted as Ru@G-CS) and their excellent performance for the upgrading of raw bio-oil were reported. Ru@G-CS composites were prepared via the direct pyrolysis of mixed glucose, melamine and RuCl3 at varied temperatures (500-800 °C). Characterization indicated that very fine Ru NPs (2.5 ± 1.0 nm) that were encapsulated within 1-2 layered N-doped graphene were fabricated on N-doped carbon sheets (CS) in Ru@G-CS-700 (pyrolysis at 700 °C). And the Ru@G-CS-700 composite was highly active and stable for hydrogenation of unstable components in bio-oil (31 samples including phenols, furfurals and aromatics) even in aqueous media under mild conditions. This work provides a new protocol to the utilization of biomass, especially for the upgrading of bio-oil.
Hydrogen Self-Sufficient Arene Reduction to Cyclohexane Derivatives Using a Combination of Platinum on Carbon and 2-Propanol
Sawama, Yoshinari,Mori, Misato,Yamada, Tsuyoshi,Monguchi, Yasunari,Sajiki, Hironao
supporting information, p. 3667 - 3670 (2016/01/25)
Various arenes have been hydrogenated using platinum on carbon in a 2-propanol-aqueous mixed solvent at 100 C without the addition of flammable hydrogen gas to give the corresponding cyclohexane derivatives. 2-Propanol plays a role as an efficient hydrogen source based on the platinum on carbon-catalyzed dehydrogenation.
Nitrous oxide-dependent iron-catalyzed coupling reactions of grignard reagents
D?hlert, Peter,Weidauer, Maik,Enthaler, Stephan
, p. 327 - 330 (2015/11/25)
The formation of carbon-carbon bonds is one of the fundamental transformations in chemistry. In this regard the application of palladium-based catalysts has been extensively investigated during recent years, but nowadays research focuses on iron catalysis, due to sustainability, costs and toxicity issues; hence numerous examples for iron-catalyzed cross-coupling reactions have been established, based on the coupling of electrophiles (R1-X, X = halide) with nucleophiles (R2-MgX). Only a small number of protocols deals with the iron-catalyzed oxidative coupling of nucleophiles (R1-MgX + R2-MgX) with the aid of oxidants (1,2-dihaloethanes). However, some issues arise with these oxidants; hence more recently the potential of the industrial waste product nitrous oxide (N2O) was investigated, because the unproblematic side product N2 is formed. Based on that, we demonstrate the catalytic potential of easily accessible iron complexes in the oxidative coupling of Grignard reagents. Importantly, nitrous oxide was essential to obtain yields up to 99% at mild conditions (e.g. 1 atm, ambient temperature) and low catalyst loadings (0.1 mol%) Excellent catalyst performance is realized with turnover numbers of up to 1000 and turnover frequencies of up to 12000 h-1. Moreover, a good functional group tolerance is observed (e.g. amide, ester, nitrile, alkene, alkyne). Afterwards the reaction of different Grignard reagents revealed interesting results with respect to the selectivity of cross-coupling product formation.
Cyclooctane metathesis catalyzed by silica-supported tungsten pentamethyl [(ΞSiO)W(Me)5]: Distribution of macrocyclic alkanes
Riache, Nassima,Callens, Emmanuel,Samantaray, Manoja K.,Kharbatia, Najeh M.,Atiqullah, Muhammad,Basset, Jean-Marie
supporting information, p. 15089 - 15094 (2015/02/19)
Metathesis of cyclic alkanes catalyzed by the new surface complex [(ΞSiO)W(Me)5] affords a wide distribution of cyclic and macrocyclic alkanes. The major products with the formula CnH2n are the result of either a ring contraction or ring expans
Catalytic hydrogenation of aromatic rings catalyzed by Pd/NiO
Wang, Yanan,Cui, Xinjiang,Deng, Youquan,Shi, Feng
, p. 2729 - 2732 (2014/01/06)
A simple and efficient heterogeneous palladium catalyst was prepared for aromatic ring hydrogenation. The catalyst was prepared by a reduction-deposition method and exhibited high activity and selectivity for the hydrogenation of a variety of substituted aromatic compounds to the corresponding cyclohexane and cyclohexanol derivatives with up to 99% yields. The catalyst was characterized by BET, TEM, XRD, XPS and ICP. Meanwhile the reusability of the catalyst was investigated, and it can be reused for several runs without significant deactivation.
Efficient and Practical Arene Hydrogenation by Heterogeneous Catalysts under Mild Conditions
Maegawa, Tomohiro,Akashi, Akira,Yaguchi, Kiichiro,Iwasaki, Yohei,Shigetsura, Masahiro,Monguchi, Yasunari,Sajiki, Hironao
experimental part, p. 6953 - 6963 (2010/02/28)
An efficient and practical arene hydrogenation procedure based on the use of heterogeneous platinum group catalysts has been developed. Rh/C is the most effective catalyst for the hydrogenation of the aromatic ring, which can be conducted in iPrOH under neutral conditions and at ordinary to medium H 2 pressures (10 atm). A variety of arenes such as alkylbenzenes, benzoic acids, pyridines, furans, are hydrogenated to the corresponding cyclohexyl and heterocyclic compounds in good to excellet yields. The use of Ru/C, less expensive than Rh/C, affords an effective and practical method for the hydrogenation of arenes including phenols. Both catalysts can be reused several times after simple filtration without any significant loss of catalytic activity.
Rhodium/graphite-catalyzed hydrogenation of carbocyclic and heterocyclic aromatic compounds
Falini, Giuseppe,Gualandi, Andrea,Savoia, Diego
experimental part, p. 2440 - 2446 (2010/02/27)
Rhodium on graphite (Rh/Gr, C24Rh) was prepared by reaction of anhydrous rhodium trichloride with potassium graphite (C8K, 3 equivalents) and used as a heterogeneous catalyst for the hydrogenation of carbocyclic and heterocyclic aromatic compounds at room temperature and 1 atm of hydrogen pressure. The effect of substitution on the benzene ring was examined in a variety of derivatives, including those with alkyl, hydroxy, alkoxy, aryloxy, carboxy, amino, nitro, acyl, chloro, or functionalized alkyl groups. Reduction of carbonyl functions of aromatic aldehydes and ketones occurred with complete or partial cleavage of the benzylic C-O bond; this cleavage also occurred in the hydrogenation of benzylic alcohols and esters. Georg Thieme Verlag Stuttgart.
A mild and facile method for complete hydrogenation of aromatic nuclei in water
Maegawa, Tomohiro,Akashi, Akira,Sajiki, Hironao
, p. 1440 - 1442 (2007/10/03)
A mild and complete hydrogenation of aromatic rings catalyzed by heterogeneous 10% Rh/C proceeds at 80 °C in water under 5 atm of H 2 pressure. This method is applicable to the hydrogenation of various carbon and heteroaromatic compounds such as alkylbenzenes, biphenyls, pyridines and furans. Georg Thieme Verlag Stuttgart.
A new convenient procedure to prepare organomanganese reagents from organic halides and activated manganese
Cahiez, Gerard,Martin, Arnaud,Delacroix, Thomas
, p. 6407 - 6410 (2007/10/03)
A new method to obtain activated manganese metal, especially attractive for large scale preparative organic chemistry, is described. The key point is the use of 2-phenylpyridine as electron carrier to reduce manganese chloride by lithium. The active manganese thus obtained was used to prepare various organomanganese reagents from organic halides. The reactivity of these reagents has been studied (acylation, 1,2- or 1,4-addition, alkylation and alkenylation).
