7443-52-9Relevant articles and documents
Transformation of organic compounds in the presence of metal complexes. IV. Hydrosilylation of 2- and 4-alkylcyclohexanones on rhodium(I) complexes
Felfoeldi, K.,Kapocsi, I.,Bartok, M.
, p. 411 - 416 (1989)
The hydrosilylation of 2- and 4-alkylcyclohexanones with Ph2SiH2 was studied under various conditions.The isomeric distribution of the resulting alcohols, i.e. the stereochemistry of the hydrosilylation, is influenced by the position and size of the alkyl groups, the catalyst concentration, the reaction temperature, and the types of ligand attached.
Addition Compounds of Alkali Metal Hydrides. 27. A General Method for Preparation of the Potassium 9-Alkoxy-9-boratabicyclononanes. A New Class of Stereoselective Reducing Agents
Brown, Herbert C.,Cha, Jin Soon,Nazer, Behrooz,Brown, Charles A.
, p. 549 - 553 (1985)
The reaction in tetrahydrofuran of potassium hydride with representative B-alkoxy-9-borabicyclononanes (B-OR-9-BBN) containing alkoxy groups with increasing steric requirements was examined in detail to establish the generality of this synthesis of the corresponding potassium 9-alkoxy-9-boratabicyclononanes (K9-OR-9-BBNH) and the stereoselectivities of these new reagents for the reduction of cyclic ketones.For R = Me and n-Bu, the reactions with potassium hydride are very fast, almost instantaneous, even at 0 deg C.However, the products are unstable and rapidly undergo redistribution, even in the presence of excess potassium hydride.Moderately hindered alkoxy derivatives, R = 2-Pr and 2-Bu, react somewhat slower (1 h at 0 deg C and 25 deg C, respectively) and the products are stable to redistribution.More hindered alkoxy derivatives, R = t-Bu, t-Am, Thx, require 24 h at 25 deg C.Even more hindered alkoxy groups, R = 3-ethyl-3-pentyl and 2,4-dimethyl-2-pentyl, require even longer reaction times and higher temperatures.All reagents show high stereoselectivities in the reduction of cyclic ketones, with the stereoselectivities generally increasing with increasing steric requirements of the alkoxy substituent.The thexyl derivative appears especially favorable, with the byproducts of the reaction readily removed from the reaction mixture.
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Dauben,Bozak
, p. 1596,1597 (1959)
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Cobalt-Nanoparticles Catalyzed Efficient and Selective Hydrogenation of Aromatic Hydrocarbons
Murugesan, Kathiravan,Senthamarai, Thirusangumurugan,Alshammari, Ahmad S.,Altamimi, Rashid M.,Kreyenschulte, Carsten,Pohl, Marga-Martina,Lund, Henrik,Jagadeesh, Rajenahally V.,Beller, Matthias
, p. 8581 - 8591 (2019/09/12)
The development of inexpensive and practical catalysts for arene hydrogenations is key for future valorizations of this general feedstock. Here, we report the development of cobalt nanoparticles supported on silica as selective and general catalysts for such reactions. The specific nanoparticles were prepared by assembling cobalt-pyromellitic acid-piperazine coordination polymer on commercial silica and subsequent pyrolysis. Applying the optimal nanocatalyst, industrial bulk, substituted, and functionalized arenes as well as polycyclic aromatic hydrocarbons are selectively hydrogenated to obtain cyclohexane-based compounds under industrially viable and scalable conditions. The applicability of this hydrogenation methodology is presented for the storage of H2 in liquid organic hydrogen carriers.
Mild and Regioselective Hydroxylation of Methyl Group in Neocuproine: Approach to an N,O-Ligated Cu6 Cage Phenylsilsesquioxane
Bilyachenko, Alexey N.,Levitsky, Mikhail M.,Khrustalev, Victor N.,Zubavichus, Yan V.,Shul'Pina, Lidia S.,Shubina, Elena S.,Shul'Pin, Georgiy B.
supporting information, p. 168 - 171 (2018/02/06)
The self-Assembly synthesis of Cu(II)-silsesquioxane involving 2,9-dimethyl-1,10-phenanthroline (neocuproine) as an additional N ligand at copper atoms was performed. The reaction revealed an unprecedented aerobic hydroxylation of only one of the two methyl groups in neocuproine to afford the corresponding geminal diol. The produced derivative of oxidized neocuproine acts as a two-centered N,O ligand in the assembly of the hexacopper cage product [Cu6(Ph5Si5O10)2·(C14H11N2O2)2] (1), coordinating two of the six copper centers in the product. Two siloxanolate ligands [PhSi(O)O]5 in the cis configuration coordinate to the rest of the copper(II) ions. Compound 1 is a highly efficient homogeneous precatalyst in the oxidation of alkanes and alcohols with peroxides.
Asymmetric Induction via a Helically Chiral Anion: Enantioselective Pentacarboxycyclopentadiene Br?nsted Acid-Catalyzed Inverse-Electron-Demand Diels-Alder Cycloaddition of Oxocarbenium Ions
Gheewala, Chirag D.,Hirschi, Jennifer S.,Lee, Wai-Hang,Paley, Daniel W.,Vetticatt, Mathew J.,Lambert, Tristan H.
supporting information, p. 3523 - 3527 (2018/03/21)
An enantioselective catalytic inverse-electron-demand Diels-Alder reaction of salicylaldehyde acetal-derived oxocarbenium ions and vinyl ethers to generate 2,4-dioxychromanes is described. Chiral pentacarboxycyclopentadiene (PCCP) acids are found to be effective for a variety of substrates. Computational and X-ray crystallographic analyses support the unique hypothesis that an anion with point-chirality-induced helical chirality dictates the absolute sense of stereochemistry in this reaction.