119-84-6Relevant academic research and scientific papers
Hydrogenation of coumarin to octahydrocoumarin over a Ru/C catalyst
Bílková, Dana,Jansa, Petr,Paterová, Iva,?erveny, Libor
, p. 957 - 960 (2015)
The production of octahydrocoumarin, which can serve as a replacement for toxic coumarin, was investigated using 5% Ru on active carbon (Ru/C) as the catalyst for the hydrogenation of coumarin. The hydrogenation was studied by optimizing the reaction conditions (pressure, solvent and coumarin concentration). The activity and selectivity of the Ru/C catalyst were compared for different solvents. The mechanism of coumarin hydrogenation was deduced. The formation of side products was explained. The optimal hydrogenation reaction conditions were: 130 °C, 10 MPa, 60 wt% coumarin in methanol, and 0.5 wt% (based on coumarin) of Ru/C catalyst. At the complete conversion of coumarin, the selectivity to the desired product was 90%.
Cerium-Catalyzed Hydrosilylation of Acrylates to Give α-Silyl Esters
Pindwal, Aradhana,Patnaik, Smita,Everett, William C.,Ellern, Arkady,Windus, Theresa L.,Sadow, Aaron D.
, p. 628 - 631 (2017)
The homoleptic organocerium complex Ce{C(SiHMe2)3}3(1) reacts with B(C6F5)3to produce the zwitterionic bis(alkyl) hydridoborato Ce{C(SiHMe2)3}2HB(C6F5)3(2). NMR and IR spectroscopy and X-ray crystallography indicate that each alkyl ligand contains two bridging Ce?H-Si interactions in both 1 and 2. Compound 2 serves as a precatalyst for the hydrosilylation of acrylates to give α-silyl esters at room temperature with a turnover number of 2200.
Bi(OTf)3-catalyzed Baeyer-Villiger oxidation of carbonyl compounds with m-CPBA
Alam, M. Mujahid,Varala, Ravi,Adapa, Srinivas R.
, p. 3035 - 3040 (2003)
An efficient method has been developed for the Baeyer-Villiger oxidation of a variety of carbonyl compounds with m-CPBA to afford the corresponding esters/lactones using bismuth triflate as catalyst. The catalyst is reused for Baeyer-Villiger oxidation without significant loss of catalytic activity for three cycles.
Synthesis of 6-, 7-, and 8-membered lactones via the nickel-catalysed electrochemical arylation of electron-deficient olefins
De Mendon?a Cavalcanti, Janesmar Camilo,Fonseca Goulart, Marilia Oliveira,Léonel, Eric,Nédélec, Jean-Yves
, p. 6343 - 6345 (2002)
A nickel-catalysed electroreductive process of arylation of α,β-unsaturated carboxylic esters has been applied to the synthesis of medium-sized lactones. Of the two possible approaches investigated in this study, the most efficient one involves first the electrochemical condensation, followed by the lactonisation.
An efficient synthesis of dihydrocoumarins
Pickett, James E.,Van Dort, Paul C.
, p. 1161 - 1164 (1992)
Dihydrocoumarins are obtained in 40 to 60% yields in one step by heating acrylic esters with an excess of a phenol in the presence of base catalysts.
Palladium nanoparticles stabilised by PTA derivatives in glycerol: Synthesis and catalysis in a green wet phase
Chahdoura, Faouzi,Favier, Isabelle,Pradel, Christian,Mallet-Ladeira, Sonia,Gómez, Montserrat
, p. 47 - 51 (2015)
Palladium nanoparticles stabilised by N-substituted 1,3,5-triaza-7-phosphaadamantane ionic ligands were synthesised from Pd(II) precursors and characterised in neat glycerol, observing an important effect of the phosphine nature in the dispersion of the nanoclusters in solution. The most homogeneously dispersed nanoparticles (Pd1a) led to the best catalytic behaviour in the benchmark Suzuki-Miyaura reaction. From this screening, Pd1a was applied in different CC cross-couplings and hydrogenation reactions, isolating the expected products in high yields (> 90%). An efficient catalyst immobilisation in glycerol was attained (up to ten runs without any sign of activity loss).
HYDROGENATION OF OXYGEN-CONTAINING HETEROCYCLIC COMPOUNDS ON GROUP VIII METALS
Karakhanov, E. A.,Dedov, A. G.,Loktev, A. S.
, p. 993 - 995 (1981)
The hydrogenation of a number of oxygen-containing heterocyclic compounds on Pt, Pd, and Rh blacks in the liquid phase at atmospheric pressure was investigated.The results are compared with data on H-D exchange with D2O and are interpreted from the point of view of the theory of ?-complex adsorption.
Heterogeneous Baeyer-Villiger oxidation of ketones using m- chloroperbenzoic acid catalyzed by hydrotalcites
Kaneda, Kiyotomi,Yamashita, Toyokazu
, p. 4555 - 4558 (1996)
Hydrotalcites promote the Baeyer-Villiger oxidation of various ketones using m-chloroperbenzoic acid to give high yields of lactones and esters.
SmI2 mediated Barbier reaction of α-fluoro ethers
Ringom, Rune,Benneche, Tore
, p. 121 - 122 (1999)
Addition of α-fluoro ethers to cyclohexanone in THF at ambient temperature has been mediated by means of SmI2.
Selective Hydrogenation of Unsaturated Carbon-Carbon Bonds in Aromatic-Containing Platform Molecules
Schwartz, Thomas J.,Lyman, Spencer D.,Motagamwala, Ali Hussain,Mellmer, Max A.,Dumesic, James A.
, p. 2047 - 2054 (2016)
The combination of chemical and biological catalysis enables the production from biomass of coumarin and dihydrocoumarin (DHC), opening new routes to the formation of fine chemicals and pharmaceutical building blocks. Each of these products requires the hydrogenation of 4-hydroxycoumarin (4HC) to 4-hydroxydihydrocoumarin (4HDHC), which, in turn, requires the reduction of an unsaturated C-C bond in the presence of an aromatic ring. Using in situ attenuated total reflection Fourier transform infrared (ATR-FTIR) spectroscopy, we show that reaction at 348 K over monometallic Pd catalysts leads to the partial reduction of the aromatic ring in 4HC, obtaining 93% selectivity for C=C bond hydrogenation at 82% 4HC conversion and with a low turnover frequency (TOF). Decreasing the Pd dispersion from 70% to 6% not only leads to an increase in the rate of 4HC hydrogenation, but it also leads to an increase in the rate of overhydrogenation. However, the formation of bimetallic PdAu nanoparticles inhibits the overhydrogenation reaction while also doubling the TOF to a value of 6 ks-1 for 4HDHC production. A bimetallic PdAu catalyst supported on SiO2 leads to 97% selectivity for C=C bond hydrogenation at 86% 4HC conversion, while an acidic support such as amorphous silica-alumina can be used to produce DHC directly from 4HC.
