17429-00-4Relevant articles and documents
Synthesis of C5-substituted AE-bicyclic analogues of lycoctonine, inuline and methyllycaconitine
Grangier, Geraldine,Trigg, William J.,Lewis, Terence,Rowan, Michael G.,Potter, Barry V. L.,Blagbrough, Ian S.
, p. 889 - 892 (1998)
We have prepared C5-substituted AE-bicyclic analogues of norditerpenoid alkaloids lycoctonine, inuline and methyllycaconitine via an acetylide anion addition strategy. Using two acetylide anions, we have regioselectively linked two cyclic ketones to acetylene.
Ductile Pd-Catalysed Hydrodearomatization of Phenol-Containing Bio-Oils Into Either Ketones or Alcohols using PMHS and H2O as Hydrogen Source
Di Francesco, Davide,Subbotina, Elena,Rautiainen, Sari,Samec, Joseph S. M.
supporting information, p. 3924 - 3929 (2018/09/14)
A series of phenolic bio-oil components were selectively hydrodearomatized by palladium on carbon into the corresponding ketones or alcohols in excellent yields using polymethylhydrosiloxane and water as reducing agent. The selectivity of the reaction was governed by the water concentration where selectivity to alcohol was favoured at higher water concentrations. As phenolic bio-oil examples cardanol and beech wood tar creosote were studied as substrate to the developed reaction conditions. Cardanol was hydrodearomatized into 3-pentadecylcyclohexanone in excellent yield. From beech wood tar creosote, a mixture of cyclohexanols was produced. No hydrodeoxygenation occurred, suggesting the applicability of the reported method for the production of ketone-alcohol oil from biomass. (Figure presented.).
Robustly supported rhodium nanoclusters: Synthesis and application in selective hydrogenation of lignin derived phenolic compounds
Fehn, Sonja,Zaheer, Muhammad,Denner, Christine E.,Friedrich, Martin,Kempe, Rhett
, p. 9252 - 9256 (2016/11/11)
The stabilization of small rhodium nanoclusters (NCs) in a polymer derived silicon carbonitride (SiCN) matrix has been reported to generate highly robust and active solid catalysts for the selective hydrogenation of phenolic compounds. An aminopyridinato Rh complex was used to modify a preceramic polymer (HTT 1800) followed by its pyrolysis at 1100 °C to afford small Rh NCs nicely dispersed over dense SiCN ceramic. For the synthesis of porous catalysts containing Rh NCs, microphase separation (followed by pyrolysis) of a diblock copolymer of HTT 1800 with hydroxy-polyethylene (PE-OH) was used. Both catalysts exhibit high activity in the hydrogenation of substituted phenols at room temperature and under low hydrogen pressure. The catalysts remained highly active and selective for six consecutive catalytic runs.
Triazolium salts as appropriate catalytic scaffolds for 1,4-additions to α,β-unsaturated carbonyls
Bratko, Ielyzaveta,Guisado-Barrios, Gregorio,Favier, Isabelle,Mallet-Ladeira, Sonia,Teuma, Emmanuelle,Peris, Eduardo,Gomez, Montserrat
, p. 2160 - 2167 (2014/04/17)
1,2,3-Triazole derivatives containing a rigid dihydroanthracenyl skeleton are suitable precursors for both organometallic and organo-based catalysts. A Rh-carbene complex and the triazolium salt efficiently catalyzed the 1,4-additions of C- and heterodonor reagents to α,β-unsaturated carbonyl substrates, respectively. Copyright
Molecular design of organic superbases, azacalix[3](2,6)pyridines: Catalysts for 1,2-and 1,4-additions
Uchida, Natsuko,Kuwabara, Junpei,Taketoshi, Ayako,Kanbara, Takaki
, p. 10631 - 10637 (2013/02/22)
The molecular design, characteristics, and catalytic activity of macrocyclic amino compounds, azacalix[3](2,6)pyridine derivatives, were studied. The introduction of an electron-donating group on the pyridine moiety and bridging amino phenyl group enabled the enhancement of the basicity of azacalix[3](2,6)pyridine up to pKBH+ = 29.5 in CD3CN. These derivatives were shown to be efficient catalysts for 1,4-addition reactions of nitroalkanes or primary alcohols to α,β-unsaturated carbonyl compounds and 1,2-addition reactions of nitroalkanes to aromatic aldehydes.
Catalytic behavior of melamine glyoxal resin towards consecutive oxidation and oxy-Michael addition
Ansari, Mohd Bismillah,Prasetyanto, Eko Adi,Lee, Jun,Park, Sang-Eon
scheme or table, p. 677 - 684 (2011/12/01)
Synthesis of melamine glyoxal resin involves a catalyst-free, one pot reaction between melamine and glyoxal in DMF. The synthesized resins have a similar morphological arrangement to that of layered materials as depicted by their XRD pattern and Raman spectra. The catalytic behavior of melamine glyoxal resin (MGR) have been studied in allylic oxidation of cyclohexene and simultaneous Michael addition. The MGR/solvent/O2 oxidant system can be regarded as a metalfree, additive-free, cost-effective and environmentally benign catalytic system. The oxidative behavior of MGR is attributed to its ability to generate in situ organic peroxide species during the course of reaction. Generation of peroxide species is confirmed by the KI/starch test and further confirmed by the complete suppression effect of TEMPO (2,2,6,6- tetramethylpiperidine-1-oxyl) over oxidation. The activity for Michael addition can be attributed to the presence of a higher content of nitrogen atoms, which serves as the active site. In oxidation, 28.1% conversion of cyclohexene with 37.19 and 62.81% selectivities for cyclohexenol and cyclohexenone were observed, respectively. In consecutive oxidation and oxy-Michael addition, 31.5% conversion of cyclohexene was observed with selectivities of 61.6% for cyclohexenone and 38.4% for alkoxy product. Springer Science+Business Media B.V. 2010.
Direct organocatalytic hydroalkoxylation of α,β-unsaturated ketones
Ramachary, Dhevalapally B.,Mondal, Rumpa
, p. 7689 - 7693 (2007/10/03)
The direct addition of a variety of alcohols to in situ activated olefins was observed in the presence of mild bifunctional amine/acid catalysts. Unlike existing methods, the reactions proceed at room temperature and in the absence of transition metals. The use of simple commercially available catalysts, amines and acids makes this an attractive method for the preparation of β-alkoxy ketones, which are prevalent targets and intermediates in organic synthesis.
Mild microwave-assisted hydrolysis of acetals under solvent-free conditions
He, Yanhong,Johansson, Martin,Sterner, Olov
, p. 4153 - 4158 (2007/10/03)
Acetals are efficiently hydrolyzed with silica gel-supported pyridinium tosylate moistened with water in solvent-free conditions under microwave irradiation. The method is efficient and mild, with acid-sensitive 3-hydroxyacetals and 3-methoxyacetals being hydrolyzed in minutes in good yields.
Application of high pressure induced by water-freezing to the Michael reaction of alcohols with α,β-enones
Hayashi, Yujiro,Nishimura, Koichi
, p. 296 - 297 (2007/10/03)
High pressure (about 200MPa), which was realized by freezing water in a sealed autoclave, has been successfully applied to a high-yield Michael reaction of alcohols and α,β-unsaturated ketones in the presence of a catalytic amount of DMAP and LiClO4. Only a moderate yield was obtained under atmospheric pressure.
P(RNCH2CH2)3N: Efficient 1,4-addition catalysts
Kisanga, Philip B.,Ilankumaran, Palanichamy,Fetterly, Brandon M.,Verkade, John G.
, p. 3555 - 3560 (2007/10/03)
The 1,4-addition of primary alcohols, higher nitroalkanes, and a Schiff's base of an α-amino ester to α,β-unsaturated substrates produces the corresponding products in moderate to excellent yields when carried out at -63 to 70°C in the presence of catalytic amounts of the nonionic strong bases P(RNCH2CH2)3N (R = Me, i-Pr, i-Bu) in isobutyronitrile. Diastereoselectivity for the anti form of the product is high in the case of the Schiff's base in the absence of lithium ion. These catalysts are easily removed from the product by either column filtration through silica gel or via aqueous workup.
