58161-11-8Relevant academic research and scientific papers
The Unimolecular Chemistry of +.: a Rationale in Terms of Hydrogen-bridged Radical Cations
Baar, Ben L. M. van,Burgers, Peter C.,Holmes, John L.,Terlouw, Johan K.
, p. 355 - 363 (1988)
By combining results from a variety of mass spectrometric techniques (metastable ion, collisional activation, collision-induced dissociative ionization, neutralization-reionization spectrometry and appearance energy measurements) and the classical method of isotopic labelling, a unified mechanism is proposed for the complex unimolecular chemistry of ionized 1,2-propanediol.The key intermediates involved are the stable hydrogen-bridged radical cations +., which were generated independently from +. (loss of C2H4) and +. (loss of CH2O), +. and the related ion-dipole complex +..The latter species serves as the precursor for the loss of CH3. and in this reaction the same non-ergodic behaviour is observed as in the loss of CH3. from the ionized enol of acetone.
The charge-assisted hydrogen-bonded organic framework (CAHOF) self-assembled from the conjugated acid of tetrakis(4-aminophenyl)methane and 2,6-naphthalenedisulfonate as a new class of recyclable Br?nsted acid catalysts
Belokon, Yuri N.,Dmitrienko, Artem O.,Gak, Alexander S.,Gerasimov, Igor S.,Kuznetsova, Svetlana A.,Larionov, Vladimir A.,Li, Han,Medvedev, Michael G.,Nelyubina, Yulia V.,North, Michael,Saghyan, Ashot S.,Smol'yakov, Alexander F.,Zhereb, Vladimir P.
supporting information, p. 1124 - 1134 (2020/07/10)
The acid–base neutralization reaction of commercially available disodium 2,6-naphthalenedisulfonate (NDS, 2 equivalents) and the tetrahydrochloride salt of tetrakis(4-aminophenyl)methane (TAPM, 1 equivalent) in water gave a novel three-dimensional charge-assisted hydrogen-bonded framework (CAHOF, F-1). The framework F-1 was characterized by X-ray diffraction, TGA, elemental analysis, and 1H NMR spectroscopy. The framework was supported by hydrogen bonds between the sulfonate anions and the ammonium cations of NDS and protonated TAPM moieties, respectively. The CAHOF material functioned as a new type of catalytically active Br?nsted acid in a series of reactions, including the ring opening of epoxides by water and alcohols. A Diels–Alder reaction between cyclopentadiene and methyl vinyl ketone was also catalyzed by F-1 in heptane. Depending on the polarity of the solvent mixture, the CAHOF F-1 could function as a purely heterogeneous catalyst or partly dissociate, providing some dissolved F-1 as the real catalyst. In all cases, the catalyst could easily be recovered and recycled.
TRANSITION METAL ISONITRILE CATALYSTS
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Page/Page column 39, (2018/11/22)
The present disclosure relates to new transition metal isonitrile compounds, processes for the production of the compounds and the use of the compounds as catalysts. The disclosure also relates to the use of the metal isonitrile compounds as catalysts for hydrogenation and transfer hydrogenation of compounds containing one or more carbon-oxygen, and/or carbon-nitrogen and/or carbon-carbon double bonds.
Phosphate modified ceria as a Br?nsted acidic/redox multifunctional catalyst
Nelson, Nicholas C.,Wang, Zhuoran,Naik, Pranjali,Manzano, J. Sebastián,Pruski, Marek,Slowing, Igor I.
supporting information, p. 4455 - 4466 (2017/03/09)
Deposition of trimethylphosphate onto ceria followed by thermal treatment resulted in the formation of surface phosphates with retention of the ceria fluorite structure. The structural and chemical properties of the phosphate-functionalized ceria were studied using 31P solid-state NMR, XPS, zeta titration, ammonia thermal desorption, pyridine adsorption, and model reactions. The introduction of phosphates generated Br?nsted acid sites and decreased the number of Lewis acid sites on the surface. The relative amount of Lewis and Br?nsted acids can be controlled by the amount of trimethylphosphate used in the synthesis. Upon deposition of Pd, the multifunctional material showed enhanced activity for the hydrogenolysis of eugenol and guaiacol compared to Pd on the unmodified ceria support. This was attributed to the cooperativity between the Lewis acid sites, which activate the substrate for dearomatization, and the redox/Br?nsted acid properties, which catalyze hydrogenolysis.
Enantiomeric Interactions and Reaction Rates: Ketalization of (S)- and (RS)-1,2-Propanediols
Wynberg, Hans,Lorand, John P.
, p. 2538 - 2542 (2007/10/02)
Aliphatic ketones, e.g., butanone, are converted nearly quantitatively to the corresponding dioxolanes (ketals) in neat (S)- or (RS)-1,2-propanediol containing dichloroacetic acid.The reactions follow the pseudo-first-order law at a given acid concentration, are inhibited by water, and proceed approximately twofold faster in (RS)-diol-O,O-d2 than in undeuterated diol.No difference in rates greater than 1percent could be detected between (S)- and (RS)-diols at identical temperatures, acid concentrations, and water concentrations.Thus, for a chiral diol molecule and the activated complex, free-energy differences are virtually the same in (S)- and (RS)-diols as solvents.Differences in interactions among identical and enantiomeric molecules, if any, are evidently matched by differences in the activated complexes.
