1119-86-4Relevant articles and documents
Rate study of proton catalyzed SmI2 reduction of 2-heptanone and 1,2-epoxydecane
Lin, Tzuen-Yeuan,Fuh, Ming-Ren,Lin, Yu-Sheng,Wen, Chang-Rong,Lin, Jia-Yung,Hu, Chiao-Ling
, p. 1223 - 1226 (2000)
Rate constants directly measured from the GC-analyzed method for SmI2 reduction of 2-heptanone and 1,2-epoxydecane in the presence of various proton sources were obtained. Water exhibits much stronger catalytic effect than methanol and t-butanol. Dependence of reaction rates on concentration of SmI2 and temperature were studied.
A recyclable dendritic osmium catalyst for homogeneous dihydroxylation of olefins
Fujita, Ken-Ichi,Yamazaki, Manabu,Ainoya, Taku,Tsuchimoto, Teruhisa,Yasuda, Hiroyuki
, p. 8536 - 8543 (2010)
A series of osmate (OsO42-) core dendrimers was prepared by an ion-exchange technique through the mixing of K 2OsO4 and a bis(quaternary ammonium bromide) core dendrimer, which consisted of poly(benzyl ether) dendron. By employing an osmate core dendrimer as a homogeneous catalyst, dihydroxylation reactions of olefins proceeded rapidly, and the dendritic osmium catalyst was recovered by reprecipitation and then reused. Furthermore, a dendritic effect on the recyclability of a catalyst was observed. In the case of asymmetric dihydroxylation reactions, the corresponding diol was obtained in a high chemical yield with a fair enantiomeric excess (ee). In this case, not only the dendritic osmium catalyst but also the chiral ligand could be recovered by reprecipitation and reused efficiently up to five times.
Sharpless,Akashi
, p. 1986 (1976)
Dihydroxylation of olefins catalyzed by polystyrene-sg-imidazolium resin-supported osmium complex
Jun, Bong-Hyun,Kim, Jong-Ho,Park, Juyoung,Kang, Homan,Lee, Sang-Hyeup,Lee, Yoon-Sik
, p. 2313 - 2316 (2008)
Osmium tetroxide was immobilized onto an imidazolium-based polymer, poly(1-methylimidazoliummethyl styrene)-surface grafted-PS (PS-sg-IM) resin. In order to characterize the polymer-imidazolium-supported osmium-complex catalysts, Fourier transform infrared (FT-IR) spectroscopy, field emission scanning electron microscopy (FE-SEM), energy dispersive X-ray microanalysis (EDX), and inductively coupled plasma-atomic emission spectroscopy (ICP-AES) experiments were carried out, and we verified that the formation of the osmium complex occurred only on the surface of the polymer support. This polymer catalysts was used in the dihydroxylation of various olefins, revealed excellent catalytic activity, and could be reused up to three times. Georg Thieme Verlag Stuttgart.
Magnetically recoverable osmium catalysts with osmium-diolate esters for dihydroxylation of olefins
Fujita, Ken-Ichi,Umeki, Satoshi,Yasuda, Hiroyuki
, p. 947 - 950 (2013)
We prepared magnetically recoverable osmium catalysts with stable osmium-diolate esters and applied them to the dihydroxylation of olefins. By employing 2 mol% of the magnetic osmium catalyst, the dihydroxylation reaction proceeded smoothly to provide the corresponding vicinal diol with a low level of osmium leaching. After completion of the dihydroxylation, the osmium catalyst was readily recovered by use of an external magnet and was recycled up to five times. Georg Thieme Verlag Stuttgart . New York.
Laminaria digitata and palmaria palmata seaweeds as natural source of catalysts for the cycloaddition of CO2 to Epoxides
Comerford, James W.,Gray, Thomas,Lie, Yann,Macquarrie, Duncan J.,North, Michael,Pellis, Alessandro
, (2019)
Seaweed powder has been found to act as an effective catalyst for the fixation of CO2 into epoxides to generate cyclic carbonates under solvent free conditions. Model background reactions were performed using metal halides and amino acids typically found in common seaweeds which showed potassium iodide (KI) to be the most active. The efficacy of the seaweed catalysts kelp (Laminaria digitata) and dulse (Palmaria palmata) was probed based on particle size, showing that kelp possessed greater catalytic ability, achieving a maximum conversion and selectivity of 63.7% to styrene carbonate using a kelp loading of 80% by weight with respect to epoxide, 40 bar of CO2, 120?C for 3 h. Maximizing selectivity was difficult due to the generation of diol side product from residual H2O found in kelp, along with a chlorinated by-product thought to form due to a high quantity of chloride salts in the seaweeds. Data showed there was loss of organic matter upon use of the kelp catalyst, likely due to the breakdown of organic compounds and their subsequent removal during product extraction. This was highlighted as the likely cause of loss of catalytic activity upon reuse of the Kelp catalyst.
REGIOSELECTIVE TITANIUM MEDIATED REDUCTIVE OPENING OF 2,3-EPOXY ALCOHOLS
Dai, Li-xin,Lou, Bo-liang,Zhang, Ying-zhi,Guo, Guang-zhong
, p. 4343 - 4346 (1986)
Lithium borohydride reduction of 2,3-epoxy alcohols was shown to yield 1,2-diols in high regioselectivity with the aid of titanium tetraisopropoxide in benzene solution.
Direct oxidative carboxylation of terminal olefins to cyclic carbonates by tungstate assisted-tandem catalysis
Calmanti, Roberto,Perosa, Alvise,Selva, Maurizio
, p. 7609 - 7619 (2021/10/12)
Tungstate catalysts are well established for olefin epoxidation reactions, while their catalytic activity for CO2 insertion in epoxides is a more recent discovery. This dual reactivity of tungstate prompted the present development of a catalytic tandem process for the direct conversion of olefins into the corresponding cyclic organic carbonates (COCs). Each of the two steps was studied in the presence of the ammonium tungstate ionic liquid catalyst-[N8,8,8,1]2[WO4]-obtained via a benign procedure starting from ammonium methylcarbonate ionic liquids. The catalytic epoxidation first step was optimised on 1-decene as model substrate, using H2O2 as benign oxidant, [N8,8,8,1]2[WO4] as catalyst and phosphoric acid as promoter affording quantitative conversion with 92% selectivity towards decene oxide. Unfortunately, the addition of CO2 from the start (auto-tandem catalysis) gave low yields of decene carbonate (10%). On the contrary, the addition of 1 atm CO2 and tetrabutyl ammonium iodide after completion of the epoxidation first step without any intermediate work-up (assisted-tandem catalysis) afforded a 94% yield in decene carbonate. The protocol could be scaled up to a 10 gram scale. The scope of the reaction was demonstrated for primary aliphatic olefins with different alkyl chain lengths (C6-C16), while cyclic and aromatic activated olefins such as cyclohexene and styrene suffered from the formation of undesired overoxidation products in the first step.
New boron reagents for cycloboration of α-olefins into boriranes under Cp2TiCl2 catalysis
Khusainova, Liliya I.,Khafizova, Leila O.,Tyumkina, Tatyana V.,Ryazanov, Kirill S.,Popodko, Natalya R.,Dzhemilev, Usein M.
, p. 73 - 77 (2018/08/23)
The one-pot cycloboration of α-olefins (oct-1-ene, dec-1-ene) for a facile access to substituted boriranes has been carried out with the use of alkyl, arylalkyl, and cycloalkyl boron dichlorides (EtBCl2, n-PentBCl2, n-HexBCl2, Ph(CH2)2BCl2, cyclo-OctBCl2, 2-norbornylBCl2) under Cp2TiCl2 catalysis.
