6138-85-8Relevant academic research and scientific papers
Chemoselective hydrogenation of the olefinic bonds using a palladium/magnesium-lanthanum mixed oxide catalyst
Kantam, Mannepalli Lakshmi,Kishore, Ramineni,Yadav, Jagjit,Sudhakar, Medak,Venugopal, Akula
supporting information; experimental part, p. 663 - 669 (2012/04/23)
A palladium/magnesium-lanthanum mixed oxide catalyst is found to be an efficient heterogeneous catalyst for the chemoselective hydrogenation of olefinic double bonds in the presence of various functional groups. The catalyst was recovered by centrifugation and reused for several cycles with consistent activity and selectivity. Copyright
Layered double hydroxides supported nano palladium: An efficient catalyst for the chemoselective hydrogenation of olefinic bonds
Lakshmi, Kantam M.,Parsharamulu,Manorama
, p. 115 - 119 (2013/01/15)
Chemoselective hydrogenation of olefinic double bonds in the presence of various functional groups using layered double hydroxides supported nanopalladium (LDH-Pd0) catalyst is described. LDH-Pd0 was recovered quantitatively by simple filtration and reused several times with consistent activity and selectivity.
Synthesis and anti-migrative evaluation of moverastin derivatives
Sawada, Masato,Kubo, Shin-Ichiro,Matsumura, Koji,Takemoto, Yasushi,Kobayashi, Hiroki,Tashiro, Etsu,Kitahara, Takeshi,Watanabe, Hidenori,Imoto, Masaya
scheme or table, p. 1385 - 1389 (2011/04/23)
Cell migration of tumor cells is essential for invasion of the extracellular matrix and for cell dissemination. Inhibition of the cell migration involved in the invasion process represents a potential therapeutic approach to the treatment of tumor metastasis; therefore, a novel series of derivatives of moverastins (moverastins A and B), an inhibitor of tumor cell migration, was designed and chemically synthesized. Among these moverastin derivatives, several compounds showed stronger cell migration inhibitory activity than parental moverastins, and UTKO1 was found to have the most potent inhibitory activity against the migration of human esophageal tumor EC17 cells in a chemotaxis cell chamber assay. Interestingly, although moverastins are considered to inhibit tumor cell migration by inhibiting farnesyltransferase (FTase), UTKO1 did not inhibit FTase, indicating that UTKO1 inhibited tumor cell migration by a mechanism other than the inhibition of FTase.
Synthesis, olfactory evaluation, and determination of the absolute configuration of the 3,4-didehydroionone stereoisomers
Serra, Stefano,Fuganti, Claudio,Brenna, Elisabetta
, p. 1110 - 1122 (2007/10/03)
The synthesis of 3,4-didehydroionone isomers 4, (+)-6, and (-)-6 and of 3,4-didehydro-7,8-dihydroionone isomers 5, (+)-7, and (-)-7 was accomplished starting from commercially available racemic α-ionone (1). Their preparation of the racemic forms 4-7 was first achieved by mean of a number of chemo- and regioselective reactions (Schemes 1 and 2). The enantio- and diastereoselective lipase-mediated kinetic acetylation of 4-hydroxy-γ- ionone (10a/10b) provided 4-hydroxy-γ-ionone (+)-10a/(±)-10b and (+)-4-(acetyloxy)-γ-ionone ((+)12b) (Scheme 3). The latter compounds were used as starting materials to prepare the 3,4-didehydro-γ-ionones (+)- and (-)-6 and the 3,4-didehydro-7,8-dihydro-γ-ionones (+)- and (-)-7 in enantiomer-enriched form. The absolute configuration of (+)-12b was determine by chemical correlation with (+)-(6S)-γ-ionone ((+)-3) and with (-)-(6S)-α-ionone ((-)-1) therefore allowing to assign the (S)-configuration to (+)-6 and (+)-7. Olfactory evaluation of the above described 3,4-didehydroionone isomers shows a significant difference between the enantiomers and regioisomers both in fragrance feature and in detection threshold (Table).
A metal nanoparticle-based supramolecular approach for aqueous biphasic reactions
Mhadgut, Shilpa C.,Palaniappan, Kumaranand,Thimmaiah, Muralidhara,Hackney, Stephen A.,Toeroek, Bela,Liu, Jian
, p. 3207 - 3209 (2007/10/03)
β-cyclodextrin immobilized on Pd nanoparticles was successfully employed as an efficient phase-transfer catalyst in aqueous biphasic hydrogenation reactions. The Royal Society of Chemistry 2005.
Bioluminescence activity of Latia luciferin analogs
Kojima, Satoshi,Maki, Shojiro,Hirano, Takashi,Ohmiya, Yoshihiro,Niwa, Haruki
, p. 4409 - 4413 (2007/10/03)
Latia luciferin analogs were synthesized and their bioluminescence activities were measured. The Latia luciferase was found to recognize strictly the 2,6,6-trimethylcyclohexene ring moiety in the luciferin structure. While the enol ether analogs exhibited no bioluminescence activity, the corresponding enol acetate analog possessed 60% activity compared to natural luciferin having an enol formate structure, implying that the initial step of the light producing reaction is an enzymatic hydrolysis to yield the corresponding enolate anion. (C) 2000 Elsevier Science Ltd.
The liquid-phase catalytic hydrogenation of β-ionone has been carried out using Pd/C catalyst
Bouchry, Naima,Aune, Jean-Pierre,Coudurier, Gisele,Rais, Taoufiq
, p. 243 - 248 (2007/10/02)
The reaction products obtained upon reduction of β-ionone were cis-dihydroionone, dihydro-β-ionone, tetrahydroionone, dihydro-α-ionone and small quantities of alcohols.Selectivity towards each product is not affected by the reaction conditions such as temperature (261-318 K), hydrogen pressure (0.11-0.53 MPa), β-ionone concentration (0.28-2.45 M) and the nature of the solvent.Under our working conditions, the order of the reaction with respect to the substrate is negative and the process is half an order in hydrogen pressure.The catalytic hydrogenation of α-ionone has been carried out in the same conditions and the selectivity of dihydro-α-ionone reaches 76percent.It appears that the conjugate ability of the system in β-ionone is responsible for the selectivity to the cis-dihydroionone (66percent) obtained during the catalytic hydrogenation of the second product. - Key words: catalytic hydrogenation / β-ionone / α-ionone / selectivity / Pd/C / apparent activation energy
Pd/AlPO4 CATALYSED SELECTIVE LIQUID-PHASE HYDROGENATION OF β-IONONE INTO CIS-DIHYDROIONONE
Bouchry, Naima,Aune, Jean-Pierre,Rais, Taoufiq
, p. 439 - 448 (2007/10/02)
The liquid-phase hydrogenation of β-ionone 1 was carried out at 302 K with 0.205 MPa of initial hydrogen pressure in methanol on Pd/AlPO4 catalyst (2-3 percent).The cis-dihydroionone 2 was obtained with a 83 percent selectivity which is independent of the degree of conversion.The reaction rate depends on the chloride concentration in the catalyst and the rection selectivity is a function of the support of the Pd.According to the Langmuir-Hinshelwood kinetic models and the Horiuti-Polanyi type mechanism, the reaction order with respect to β-ionone concentration is negative and of one half order with respect to the hydrogen pressure.The comparison with results obtained over Pd/C catalyst and those obtained in the catalytic hydrogenation of α-ionone suggests that the catalytic hydrogenation of β-ionone could take place on two different active sites of the Pd.
Colloidal palladium, easily formed in organic solvents, is a highly active and stable catalyst for selective hydrogenations and dehydrohalogenations
Fowley, Lissa A.,Michos, Demetrius,Luo, Xiao-Liang,Crabtree, Robert H.
, p. 3075 - 3078 (2007/10/02)
Collidal Pd formed in organic solvents from Pd(hfacac)2 and silane or an Si-H- containing polymer is an active, stable and selective catalyst for hydrogenation and dehydrohalogenation.
Chemoselectivity in Catalytic Transfer Hydrogenation - Reduction of Alkenes and Alkynes with the H2PO2-NH4+*H2O/Pd-C System
Khai, Bui The,Arcelli, Antionio
, p. 2265 - 2268 (2007/10/02)
The H2PO2-*H2O/Pd-C system acts as an unusually powerful reducing agent, which is able to reduce cyclooctene to cyclooctane, Δ9,10-octalin to decalins, α- and β-pinenes to pinanes at room temperature in high yield without the formation of byproducts.This system reduces each of these compounds or partly (alkynes to alkenes), depending on the competition between the transfer hydrogenation to give alkanes and the protonolysis to give hydrogen gas on the palladium catalyst. - Key Words: Chemoselectivity/ Protonolysis/ Transfer hydrogenation/ Alkenes, reduction of/ Alkynes, reduction of
