646-31-1Relevant articles and documents
Ni/Co-catalyzed homo-coupling of alkyl tosylates
Komeyama, Kimihiro,Tsunemitsu, Ryusuke,Michiyuki, Takuya,Yoshida, Hiroto,Osaka, Itaru
, (2019/05/02)
A direct reductive homo-coupling of alkyl tosylates has been developed by employing a combination of nickel and nucleophilic cobalt catalysts. A single-electron-transfer-type oxidative addition is a pivotal process in the well-established nickel-catalyzed coupling of alkyl halides. However, the method cannot be applied to the homo-coupling of ubiquitous alkyl tosylates due to the high-lying σ*(C–O) orbital of the tosylates. This paper describes a Ni/Co-catalyzed protocol for the activation of alkyl tosylates on the construction of alkyl dimers under mild conditions.
Electron transfer-induced reduction of organic halides with amines
Fukuyama, Takahide,Fujita, Yuki,Miyoshi, Hayato,Ryu, Ilhyong,Kao, Shih-Chieh,Wu, Yen-Ku
supporting information, p. 5582 - 5585 (2018/06/04)
Reduction of a variety of organo halides was examined by using amines as a sacrificial hydrogen source. UV light-induced reduction of vinyl and aryl halides with triethylamine proceeded smoothly to give the corresponding reduced products. High temperature heating also caused the reduction and DABCO (1,4-diazabicyclo[2.2.2]octane) also served as a good reducing reagent.
NMR-based molecular ruler for determining the depth of intercalants within the lipid bilayer. Part III: Studies on keto esters and acids
Afri, Michal,Alexenberg, Carmit,Aped, Pinchas,Bodner, Efrat,Cohen, Sarit,Ejgenburg, Michal,Eliyahu, Shlomi,Gilinsky-Sharon, Pessia,Harel, Yifat,Naqqash, Miriam E.,Porat, Hani,Ranz, Ayala,Frimer, Aryeh A.
, p. 105 - 118 (2015/02/19)
The development of "molecular rulers" would allow one to quantitatively locate the penetration depth of intercalants within lipid bilayers. To this end, an attempt was made to correlate the 13C NMR chemical shift of polarizable "reporter" carbons (e.g., carbonyls) of intercalants within DMPC liposomal bilayers - with the polarity it experiences, and with its Angstrom distance from the interface. This requires families of molecules with two "reporter carbons" separated by a known distance, residing at various depths/polarities within the bilayer. For this purpose, two homologous series of dicarbonyl compounds, methyl n-oxooctadecanoates and the corresponding n-oxooctadecanoic acids (n = 4-16), were synthesized. To assist in assignment and detection several homologs in each system were prepared 13C-enriched in both carbonyls. Within each family, the number of carbons and functional groups remains the same, with the only difference being the location of the second ketone carbonyl along the fatty acid chain. Surprisingly, the head groups within each family are not anchored near the lipid-water interface, nor are they even all located at the same depth. Nevertheless, using an iterative best fit analysis of the data points enables one to obtain an exponential curve. The latter gives substantial insight into the correlation between polarity (measured in terms of the Reichardt polarity parameter, ET(30)) and penetration depth into the liposomal bilayer. Still missing from this curve are data points in the moderate polarity range.
Dilithium tetrachlorocuprate(II) catalyzed oxidative homocoupling of functionalized grignard reagents
Hua, Si-Kai,Hu, Qiu-Peng,Ren, Jiangmeng,Zeng, Bu-Bing
, p. 518 - 526 (2013/03/29)
An efficient procedure is described for the oxidative homocoupling of functionalized Grignard reagents using a catalytic amount of dilithium tetrachlorocuprate(II) (CuLi2Cl4) in the presence of pure oxygen gas. This method is applied successfully to a variety of aryl, heteroaryl, alkyl, alkenyl and alkynyl halides, which are converted into the corresponding homocoupled products in good to excellent yields. Georg Thieme Verlag Stuttgart · New York.
Novel reducing properties of a series of lanthanoid metals in the presence of SmI2
Tomisaka, Yuri,Yoshimura, Aya,Nomoto, Akihiro,Sonoda, Motohiro,Ogawa, Akiya
, p. 43 - 48 (2013/03/13)
The reduction of dodecyl iodide, as model compound, with a series of lanthanoid (Ln) metals in the presence of catalytic amounts of samarium diiodide (SmI2) has been investigated in detail. The reducing activity of SmI2/Ln and the kinds of reduced products were found to be dependent on the individual Ln, but not on SmI2.
Efficient heterogeneous dual catalyst systems for alkane metathesis
Huang, Zheng,Rolfe, Eleanor,Carson, Emily C.,Brookhart, Maurice,Goldman, Alan S,El-Khalafy, Sahar H.,Roy MacArthur, Amy H.
experimental part, p. 125 - 135 (2010/06/20)
A fully heterogeneous and highly efficient dual catalyst system for alkane metathesis (AM) has been developed. The system is comprised of an alumina-supported iridium pincer catalyst for alkane dehydrogenation/olefin hydrogenation and a second heterogeneous olefin metathesis catalyst. The iridium catalysts bear basic functional groups on the aromatic backbone of the pincer ligand and are strongly adsorbed on Lewis acid sites on alumina. The heterogeneous systems exhibit higher lifetimes and productivities relative to the corresponding homogeneous systems as catalyst/catalyst interactions and bimolecular decomposition reactions are inhibited. Additionally, using a two-pot device, the supported Ir catalysts and metathesis catalysts can be physically separated and run at different temperatures. This system with isolated catalysts shows very high turnover numbers and is selective for the formation of high molecular weight alkanes.
Glassy carbon modified by a silver-palladium alloy: cheap and convenient cathodes for the selective reductive homocoupling of alkyl iodides
Poizot, Philippe,Jouikov, Viatcheslav,Simonet, Jacques
body text, p. 822 - 824 (2009/05/07)
Micrometer-thick layers of silver-palladium alloy were elaborated in order to modify the surface of glassy carbon electrodes. Such a surface modification can be readily achieved via a preliminary silver galvanostatic deposit onto carbon followed by a 'palladization' step, thanks to a simple immersion in acidic PdII-based solutions producing a displacement reaction. The as-prepared metallic interfaces exhibit outstanding catalytic capabilities especially in the cleavage of carbon-halogen bonds while being chemically/electrochemically quite stable and relatively inexpensive. More specifically, the use of such glassy carbon/Ag-Pd electrodes in dimethylformamide (DMF) containing tetraalkylammonium salts (TAA+X-) makes the one-electron reductions of primary alkyl iodides possible; this reduction leads to the formation of homodimers in high yields. Formation of a free radical as transient resulted from the homocoupling reaction.
On the potentially excellent reducing ability of a series of low-valent rare earths induced by photoirradiation
Tomisaka, Yuri,Nomoto, Akihiro,Ogawa, Akiya
scheme or table, p. 584 - 586 (2009/05/11)
Mixed systems of a series of rare earth metals such as La, Ce, Pr, Nd, Sm, Eu, and Yb and their low-valent rare earth diiodides exhibit excellent reducing ability toward the reductive deiodation from 1-iodododecane as a model compound compared with their single systems. More importantly, under photoirradiation conditions, the C-I bond reduction using 'Ln/LnI2' takes place efficiently in refluxing THF, even in the cases of heavy rare earths such as Gd, Tb, Dy, Ho, Er, and Tm.
DEGRADATION OF POLYCYCLIC AROMATIC HYDROCARBONS TO RENDER THEM AVAILABLE FOR BIODEGRADATION
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Page/Page column 5-8; 15-16, (2008/12/07)
A method for the degradation of polycyclic aromatic compounds is disclosed that involves dissolving ozone in a bipolar solvent comprising a non-polar solvent in which is of sufficiently non-polar character to solubilized the polycyclic aromatic compounds, and a polar-water-compatible solvent which is fully miscible with the non-polar solvent to form a single phase with the non-polar solvent. The bipolar solvent with dissolved ozone is contacted with the polycyclic aromatic compounds to solubilize the polycyclic aromatic compounds and react the dissolved polycyclic aromatic compounds with the ozone to degrade the dissolved polycyclic aromatic compounds to oxygenated intermediates. The bipolar solvent is then mixed with sufficient water to form separate non-polar and polar phases, the non-polar phase comprising the non-polar solvent and the polar phase comprising the non-polar solvent and the oxygenated intermediates. The polar phase is then diluted and incubated with bacteria to biodegrade the oxygenated intermediates.
Nanosized iron- or copper-catalyzed homocoupling of aryl, heteroaryl, benzyl, and alkenyl grignard reagents
Moglie, Yanina,Mascaro, Evangelina,Nador, Fabiana,Vitale, Cristian,Radivoy, Gabriel
experimental part, p. 3861 - 3874 (2009/04/11)
Under very mild reaction conditions, iron or copper nanoparticles efficiently promoted the homocoupling of different Grignard reagents in tetrahydrofuran at room temperature. The nanosized iron or copper particles were generated in situ in a simple and economical way from commercially available FeCl2 or CuCl2, respectively, an excess of lithium powder, and a catalytic amount (5 mol%) of 4,4′-di-tert-butylbiphenyl (DTBB) as electron carrier. The reaction of a series of aryl, heteroaryl, benzyl, and alkenyl Grignard reagents in the presence of a substoichiometric amount of the iron or copper nanoparticles led to the formation of the corresponding homocoupling products in good yield. Copyright Taylor & Francis Group, LLC.