630-02-4Relevant articles and documents
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.
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.
METHOD FOR THE PRODUCTION OF PRIMARY LONG-CHAIN ALCOHOLS
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Page/Page column 10-11, (2010/02/15)
The invention relates to a method for the production of linear long-chain alcohols with 20 to 40 carbon atoms by means of a growth reaction with ethylene on aluminium compounds.
Enantioselective total synthesis of Irniine and Bgugaine, bioactive 2-alkylpyrrolidine alkaloids
Jossang, Akino,Melhaoui, Ahmed,Bodo, Bernard
, p. 755 - 766 (2007/10/03)
An asymmetric total synthesis of the 2-(R)-alkylpyrrolidines, (-)-irniine (1a) and (-)-bgugaine (1b), toxic and antibiotic components of the tubers of Arisarum vulgare, and (+)-(S)-irniine (1c), was carried out by condensation of the corresponding 4-oxoalkanoic acid (9) with chiral phenylglycinol. Acids (9) were prepared from a hetero-organocuprate (I) complex, generated by reaction of methylcopper (I) with alkylmagnesium bromides and methyl chlorocarbonylpropionate. Alkaloids (1a, 1b and 1c) displayed anti Gram(+) bacterial (MIC 12.5 - 50 μg/ml) and antifungal (MIC 6.25 - 50 μg/ml) activities.
Bifunctional compounds from reaction of alkoxy hydroperoxides with metal salts
Cardinale,Laan,Van Der Steen,Ward
, p. 6051 - 6054 (2007/10/02)
Alkoxy hydroperoxides, obtained by ozonizing olefins in alcoholic solution, were treated with ferrous sulfate. C-C bond scission and radical formation was followed by dimerization of the radicals formed. Ozonides reacted similarly. Acyclic and cyclic olefins, including a cyclic enol ether, gave rise to a range of α,ω-disubstituted products in modest yields. By using ferric chloride, ω-chloro esters were obtained from the alkoxy hydroperoxides derived from olefinic esters.
The Reductive Coupling of Organic Halide Using Hydrazine and a Palladium Catalyst.II. Homocoupling of 1-Iodoalkanes
Nakajima, Riichiro,Morita, Kazuhiro,Hara, Tadashi
, p. 3599 - 3600 (2007/10/02)
The hydrogenolysis and dimerization of iodoalkanes were catalyzed by Pd in the presence of an appropriate reducing agent.Hydrazine was found to be effective for the coupling of 1-iodoeicosane to give tetracontane, C40H82, in a 74 percent yield.The yield of the coupling product decreased with the decrease of the number of the carbon atoms in the 1-iodoalkanes.Both alkylhydrazines and alkenes were shown not to take part in the reaction as a reaction intermediate.
