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Sumitomo catalysts

This method of asymmetric cyclopropanation using copper catalysts which are chirally modified with salicylaldimines of optically active amines has been intensively investigated and numerous modifications of the ligands have been tested24-40-43. The use of chiral amino alcohols derived from amino acids is exceptionally successful. Thus, 2-methylpropene with ethyl diazoacetate in the presence of R-7644 (Sumitomo catalyst) gives ethyl (LS)-2,2-dimethyl-1-cyclopropanecarboxylate (2) with 92% ee, on an industrial scale24. This compound is used as a precursor of cilastm, an enzyme inhibitor. [Pg.448]

Figure 1.14 Critical properties of Sumitomo s titanium molecular sieve. (Left) Essential chemical and morphological properties. (Right) Relative contributions of mesopores to total surface area for a regular TS-1 sample and for the Sumitomo catalyst./Idapted from Ref. (263), with permission from Sumitomo Chemical Co. Ltd. Figure 1.14 Critical properties of Sumitomo s titanium molecular sieve. (Left) Essential chemical and morphological properties. (Right) Relative contributions of mesopores to total surface area for a regular TS-1 sample and for the Sumitomo catalyst./Idapted from Ref. (263), with permission from Sumitomo Chemical Co. Ltd.
Patents claiming specific catalysts and processes for thek use in each of the two reactions have been assigned to Japan Catalytic (45,47—49), Sohio (50), Toyo Soda (51), Rohm and Haas (52), Sumitomo (53), BASF (54), Mitsubishi Petrochemical (56,57), Celanese (55), and others. The catalysts used for these reactions remain based on bismuth molybdate for the first stage and molybdenum vanadium oxides for the second stage, but improvements in minor component composition and catalyst preparation have resulted in yields that can reach the 85—90% range and lifetimes of several years under optimum conditions. Since plants operate under more productive conditions than those optimum for yield and life, the economically most attractive yields and productive lifetimes maybe somewhat lower. [Pg.152]

Sumitomo Chemical Co. (98—100) and Mitsubishi Kasei Co. (101) have patented single-step catalysts containing niobium and palladium. A Sumitomo example reports 93.5% MIBK selectivity at 41.8% acetone conversion and conditions of 160°C and 2 MPa. Other significant processes have been reported (60,102—110). [Pg.492]

MIBK Direct Conversion ofMcetone over Heterogeneous Catalyst-Sumitomo, Process Evaluation Research Planning (PERP), Topical Reports, Vol. Ill, Chem Systems Inc., Tarrytown, NY, 1988. [Pg.502]

In the 1970s, Solvay iatroduced an advanced TiCl catalyst with high activity and stereoregulahty (6). When this catalyst was utilized ia Hquid monomer processes, the level of atactic polymer was sufftciendy low so that its removal from the product was not required. Catalyst residues were also reduced so that simplified systems for post-reactor treatment were acceptable. Sumitomo has developed a Hquid monomer process, used by Exxon (United States), ia which polymer slurry is washed ia a countercurrent column with fresh monomer and alcohol to provide highly purified polymer (128). [Pg.415]

Syndiotactic polypropylene first became available in the 1990s (Fina, Mitsui Toastu, Sumitomo) and more recently has been marketed by Dow. Currently this polymer is more expensive than other polypropylenes both because of catalyst costs and the small scale of production. [Pg.259]

Solid super bases, prepared by successive treatment of y-alumina with alkali metal hydroxide and alkali metal, are highly active catalysts for reactions involving reactive carbanions, and have been commercialised by Sumitomo (Suzukamo et al, 1997). For example, t.vobutylbenzene, the. starting material for ibuprofen (see earlier) is produced by side-chain alkylation of toluene with propylene over a K/KOH/AI2O3 catalyst (Eqn. (14)). [Pg.45]

The catalyst system reported by Nozaki and Noyori was developed into a commercial process by Aratani and co-workers (14) at Sumitomo. The original salicyl-... [Pg.7]

Recently, the Sumitomo Chemical Co., Ltd. developed the vapour-phase Beckmann rearrangement process for the production of 8-caprolactam. In the process, cyclohexanone oxime is rearranged to e-caprolactam by using a zeolite as a catalyst instead of sulfuric acid. EniChem in Italy developed the ammoximation process that involves the direct production of cyclohexanone oxime without producing any ammonium sulfate. The Sumitomo Chemical Co., Ltd. commercialized the combined process of vapour-phase Beckmann rearrangement and ammoximation in 2003 ". [Pg.472]

The authors gratefully acknowledge the CREST Program Nano Catalyst of JSTand NEDO for financial support. They are also grateful to Sumitomo Trading Co. and Mr Uemura Masaaki for financial support and continuous cooperation during this study. [Pg.85]

The primary product in the slurry units is HDPE with MDPE as a secondary product. With single-site catalysts production of mLLDPE in slurry loop reactors is also possible. Today for example, Chevron Phillips, BP Solvay, Basell, Borealis and Sumitomo Mitsui have their own slurry process technology-... [Pg.19]

One of the earliest examples of such catalysis was demonstrated in 1966 by the Japanese chemist Hitosi Nozaki, who reacted styrene and ethyl diazoacetate in the presence of a chiral Schiffbase-Cu11 complex [72-74], Although the initial enantios-electivity was modest (<10% ee), the principle was proven. Some years later, the companies Sumitomo and Merck used similar copper catalysts for asymmetric cyclopropanation on a multikilogram scale, in the production of various insecticides and antibiotics [75]. One of Nozaki s PhD students at that time was Rioji Noyori, who later developed the BINAP asymmetric hydrogenation catalysts for which he received the 2001 Nobel Prize in Chemistry [7[. [Pg.95]

The second important use of superbases is side-chain alkylation of aromatic compounds [22, 34]. In these reactions a benzyl anion generated by the superbase catalyst subsequently attacks olefins such as ethene or propene as a nucleophile. The result of such a nucleophilic addition of a carbanion is side-chain alkylation of the arene by ethene. The reaction was commercialized by Sumitomo for the side-chain alkylation of cumene (Scheme 5, a) [34]. [Pg.414]

One of the industrially important dimerization reactions that involves the use of homogeneous catalysts is the dimerization of propylene. Dimerization of propylene produces mixtures of the isomers of methyl pentenes, hexenes, and 2,3-dimethyl butene and is practiced by the Institut Francis du Petrole (IFP), Sumitomo, and British Petroleum (BP). The methyl pentenes and hexenes are used as gasoline additives. Dimethylbutene is used in the fragrance and the agrochemical industries. [Pg.142]

N-Free A process for removing nitrates from industrial wastewaters, N-Free has two stages. In the first, nitrates are reduced to nitrites using hydrazine and a fixed-bed copper catalyst. In the second, the nitrite is reduced to elemental nitrogen using amidosulfonic acid as the reductant. Developed by Sumitomo Metal Mining Company and piloted in 2002. [Pg.254]

Sumitomo Chemical Co., Ltd. Isobutylene MTBE High-purity isobutylene (99.9%) is produced from MTBE with a high conversion and selectivity catalyst 4 1996... [Pg.125]

Sumitomo Chemical Co.,Ltd. Polypropylene Propylene Gas phase processes with proprietary high-performance catalyst 9 1994... [Pg.132]

The first commercial applicahon, made possible by an agreement between EniChem and Sumitomo, went on-stream in 2003 in Japan, within the context of an integrated process for the produchon of e-caprolactam by a new salt-free technology (ca GOOOOta ). Actually, besides the ammoximation step, no major byproduct is produced even in the gas-phase rearrangement carried out on silicalite-1 as the catalyst. On the whole, the ammonium sulfate is no longer a burden and the gaseous emissions too are drashcally reduced. [Pg.735]

Regioselective dimerization of propene to 2,3-dimethylbutenes (DMBs) is currently operated by Sumitomo and BP Chemicals. Both use P(cyclohexyl)3 as the bulky ligand. In the Sumitomo process [7] very high selectivities in DMBs (up to 85 %) are obtained at 20-50 °C, thanks to a sophisticated, highly efficient, Ziegler-type catalyst system (ten times more efficient than those of conventional catalysts) and by using toluene as a solvent. Isomerization of 2,3-dimethyl-1-butene (DMB-1) into 2,3-dimethyl-2-butene (DMB-2) takes place directly in... [Pg.257]


See other pages where Sumitomo catalysts is mentioned: [Pg.412]    [Pg.449]    [Pg.412]    [Pg.449]    [Pg.1541]    [Pg.268]    [Pg.268]    [Pg.113]    [Pg.41]    [Pg.37]    [Pg.132]    [Pg.50]    [Pg.267]    [Pg.431]    [Pg.280]    [Pg.54]    [Pg.303]    [Pg.877]    [Pg.23]    [Pg.414]    [Pg.363]    [Pg.578]    [Pg.12]    [Pg.98]    [Pg.210]    [Pg.62]    [Pg.1363]    [Pg.554]   
See also in sourсe #XX -- [ Pg.412 ]




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