10203-28-8Relevant academic research and scientific papers
From Alkanes to Carboxylic Acids: Terminal Oxygenation by a Fungal Peroxygenase
Olmedo, Andrés,Aranda, Carmen,del Río, José C.,Kiebist, Jan,Scheibner, Katrin,Martínez, Angel T.,Gutiérrez, Ana
, p. 12248 - 12251 (2016)
A new heme–thiolate peroxidase catalyzes the hydroxylation of n-alkanes at the terminal position—a challenging reaction in organic chemistry—with H2O2as the only cosubstrate. Besides the primary product, 1-dodecanol, the conversion of dodecane yielded dodecanoic, 12-hydroxydodecanoic, and 1,12-dodecanedioic acids, as identified by GC–MS. Dodecanal could be detected only in trace amounts, and 1,12-dodecanediol was not observed, thus suggesting that dodecanoic acid is the branch point between mono- and diterminal hydroxylation. Simultaneously, oxygenation was observed at other hydrocarbon chain positions (preferentially C2 and C11). Similar results were observed in reactions of tetradecane. The pattern of products formed, together with data on the incorporation of18O from the cosubstrate H218O2, demonstrate that the enzyme acts as a peroxygenase that is able to catalyze a cascade of mono- and diterminal oxidation reactions of long-chain n-alkanes to give carboxylic acids.
Hydrofunctionalization of Olefins to Higher Aliphatic Alcohols via Visible-Light Photocatalytic Coupling
Bao, Jingxian,Fan, Yonghui,Zhang, Shuyi,Zhong, Liangshu,Wu, Minghong,Sun, Yuhan
, (2019)
Abstract: An atomically economical green protocol for the hydrofunctionalization of olefins to higher aliphatic alcohols with 100% anti-Markovnikov regioselectivity was developed via visible-light photocatalytic coupling. This method employs cheap, readily available and abundant methanol as both the C1 feedstock and the hydrogen source under visible light irradiation over CdS photocatalyst. A wide scope of olefin substrates could be hydrofunctionalized successfully to the corresponding higher alcohols with high selectivity. Besides alcohol, acetone and acetonitrile can also couple with olefins to generate the corresponding hydrofunctionalization products, suggesting promising potential industrial application. Graphical Abstract: [Figure not available: see fulltext.] Hydrofunctionalization of olefins to value-added chemicals with high selectivity was achieved via visible-light photocatalytic cross-coupling.
A manganese-containing molecular sieve catalyst designed for the terminal oxidation of dodecane in air
Raja, Robert,Thomas, John Meurig
, p. 1841 - 1842 (1998)
MnIII ions that replace a few percent of the framework AlIII sites in a microporous aluminophosphate - number 18, with a pore aperture of 3.8 A - function as catalytically active centres for the selective oxidation of dodecane preferentially at C1 and C2.
Synergistic Effect in Ir- or Pt-Doped Ru Nanoparticles: Catalytic Hydrogenation of Carbonyl Compounds under Ambient Temperature and H2Pressure
Ichikuni, Nobuyuki,Masuda, Shinya,Matsuda, Shotaro,Takano, Shinjiro,Tsukuda, Tatsuya
, p. 10502 - 10507 (2021)
Poly(vinylpyrrolidone) (PVP)-stabilized Ir- or Pt-doped (10 at. ?%) Ru NPs with the average diameters of 1.3-1.5 nm (RuIr or RuPt) were prepared by a coreduction of the corresponding metal precursors. RuIr and RuPt showed remarkable activity for the hydrogenation of aromatic, cyclic, and aliphatic carbonyl compounds at 30 °C under 0.2 MPa of H2, whereas the monometallic NPs of Ru, Ir, and Pt did not show any activity under the same conditions. In particular, RuPt converted the aliphatic aldehyde and cyclohexanone to the corresponding alcohols at 30 °C under atmospheric H2 pressure. Remarkable synergistic effects were ascribed to the provision of highly active sites for H2 and enhancement of the nucleophilicity of the adsorbed hydrides.
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
, p. 2892 - 2896 (2018)
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.
Sustainable radical reduction through catalyzed hydrogen atom transfer reactions (CHAT-reactions)
Gans?uer, Andreas,Otte, Matthias,Piestert, Frederik,Fan, Chun-An
, p. 4984 - 4991 (2009)
A system with coupled catalytic cycles is described that allows radical reduction by catalyzed hydrogen atom transfer (CHAT) from transition metal hydrides. These intermediates are generated through H2 activation. Radical generation is carried out by titanocene catalyzed electron transfer to epoxides. The reaction provides a novel entry into the atom-economical reduction of radicals that has long been considered as a critical issue for the industrial application of radical chemistry.
“Inverse” Frustrated Lewis Pairs: An Inverse FLP Approach to the Catalytic Metal Free Hydrogenation of Ketones
Mummadi, Suresh,Brar, Amandeep,Wang, Guoqiang,Kenefake, Dustin,Diaz, Rony,Unruh, Daniel K.,Li, Shuhua,Krempner, Clemens
, p. 16526 - 16531 (2018)
For the first time have boron-containing weak Lewis acids been demonstrated to be active components of Frustrated Lewis Pair (FLP) catalysts in the hydrogenation of ketones to alcohols. Combining the organosuperbase (pyrr)3P=NtBu with the Lewis acid 9-(4-CF3-C6H4)-BBN generated an “inverse” FLP catalyst capable of hydrogenating a range of aliphatic and aromatic ketones including N-, O- and S-functionalized substrates and bio-mass derived ethyl levulinate. Initial computational and experimental studies indicate the mechanism of catalytic hydrogenation with “inverse” FLPs to be different from conventional FLP catalysts that contain strong Lewis acids such as B(C6F5)3.
Hydrofunctionalization of olefins to value-added chemicals: Via photocatalytic coupling
Fan, Yonghui,Li, Shenggang,Bao, Jingxian,Shi, Lei,Yang, Yanzhang,Yu, Fei,Gao, Peng,Wang, Hui,Zhong, Liangshu,Sun, Yuhan
, p. 3450 - 3456 (2018)
A green strategy was developed for the synthesis of various value-added chemicals using methanol, acetonitrile, acetic acid, acetone and ethyl acetate as the hydrogen source by coupling them with olefins over heterogeneous photocatalysts. A radical coupling mechanism was proposed for the hydrofunctionalization of olefins with methanol to higher aliphatic alcohols over the Pt/TiO2 catalyst as the model reaction. C-H bond cleavage and C-C bond formation between photogenerated radicals and terminal olefins were accomplished in a single reaction at high efficiency. Our approach is atomically economical with high anti-Markovnikov regioselectivity and promising application potential under mild reaction conditions.
Titanocenes as Photoredox Catalysts Using Green-Light Irradiation
Flowers, Robert A.,Gans?uer, Andreas,Hilche, Tobias,Oloyede, Ugochinyere N.,Rietdijk, Niels R.,Slak, Daniel,Zhang, Zhenhua
, p. 9355 - 9359 (2020)
Irradiation of Cp2TiCl2 with green light leads to electronically excited [Cp2TiCl2]*. This complex constitutes an efficient photoredox catalyst for the reduction of epoxides and for 5-exo cyclizations of suitably unsaturated epoxides. To the best of our knowledge, our system is the first example of a molecular titanium photoredox catalyst.
Failure and Redemption of Statistical and Nonstatistical Rate Theories in the Hydroboration of Alkenes
Bailey, Johnathan O.,Singleton, Daniel A.
, p. 15710 - 15723 (2017)
Our previous work found that canonical forms of transition state theory incorrectly predict the regioselectivity of the hydroboration of propene with BH3 in solution. In response, it has been suggested that alternative statistical and nonstatistical rate theories can adequately account for the selectivity. This paper uses a combination of experimental and theoretical studies to critically evaluate the ability of these rate theories, as well as dynamic trajectories and newly developed localized statistical models, to predict quantitative selectivities and qualitative trends in hydroborations on a broader scale. The hydroboration of a series of terminally substituted alkenes with BH3 was examined experimentally, and a classically unexpected trend is that the selectivity increases as the alkyl chain is lengthened far from the reactive centers. Conventional and variational transition state theories can predict neither the selectivities nor the trends. The canonical competitive nonstatistical model makes somewhat better predictions for some alkenes but fails to predict trends, and it performs poorly with an alkene chosen to test a specific prediction of the model. Added nonstatistical corrections to this model make the predictions worse. Parametrized Rice-Ramsperger-Kassel-Marcus (RRKM)-master equation calculations correctly predict the direction of the trend in selectivity versus alkene size but overpredict its magnitude, and the selectivity with large alkenes remains unpredictable with any parametrization. Trajectory studies in explicit solvent can predict selectivities without parametrization but are impractical for predicting small changes in selectivity. From a lifetime and energy analysis of the trajectories, "localized RRKM-ME" and "competitive localized noncanonical" rate models are suggested as steps toward a general model. These provide the best predictions of the experimental observations and insight into the selectivities.
