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Acetic anhydride ruthenium catalyst

Carbonylation of Methyl Acetate on Ni/A.C. Catalysts. Table II shows the catalytic activities of nickel and platinum group metals supported on activated carbon for the carbonylation of methyl acetate. Ruthenium, palladium, or iridium catalysts showed much lower activity for the synthesis of acetic anhydride than the nickel catalyst. In contrast, the rhodium catalyst, which has been known to exhibit an excellent carbonylation activity in the homogeneous system (1-13), showed nearly the same activity as the nickel catalyst but gave a large amount of acetic acid. [Pg.179]

Deacetylation of 80 in methanolic sodium methoxide and successive O-isopropyli-denation with 2,2-dimethoxypropane gave 2-0-acetyl-3,4-O-isopropylidene-l,6-an-hydro-pseudo-p-DL-galactopyranose (81), after acetylation. Removal of the acetyl group of 81, followed by oxidation with ruthenium tetroxide and sodium metaperiodate afforded the 2-oxo derivative (82). Catalytic hydrogenation of 82 under the presence of platinum catalyst and acetolysis in a mixture of acetic acid, acetic anhydride and sulfuric acid gave pseudo-P-DL-talopyranose pentaacetate (83) [25] (Scheme 17). [Pg.266]

A mixed oxide of ruthenium, copper, iron and alumnium has been developed as a catalyst for the synthesis of aldehydes and ketones from alcohols.258 Oxidation of chiral secondary 1,2-diols with 2,3-dichloro-5,6-dicyano-l,4-benzoquinone under ultrasound wave promotion leads to the selective oxidation of benzylic or allylic hydroxyl group. The configuration of the adjacent chiral centre is retained.259 The kinetics of oxidation of ethylbenzene in the presence of acetic anhydride have been studied.260... [Pg.115]

A process for the coproduction of acetic anhydride and acetic acid, which has been operated by BP Chemicals since 1988, uses a quaternary ammonium iodide salt in a role similar to that of Lil [8]. Beneficial effects on rhodium-complex-catalyzed methanol carbonylation have also been found for other additives. For example, phosphine oxides such as Ph3PO enable high catalyst rates at low water concentrations without compromising catalyst stability [40—42]. Similarly, iodocarbonyl complexes of ruthenium and osmium (as used to promote iridium systems, Section 3) are found to enhance the activity of a rhodium catalyst at low water concentrations [43,44]. Other compounds reported to have beneficial effects include phosphate salts [45], transition metal halide salts [46], and oxoacids and heteropolyacids and their salts [47]. [Pg.10]

Acetalization and deacetalization can be carried out in iron, ruthenium, and platinum catalysts. Anhydrous ferric chloride with acetic anhydride transforms... [Pg.363]

An efficient one-pot procedure for the iV-monomethylation of primary amines has been reported the method involves formylation with acetic formic anhydride followed by borane methyl sulphide reduction. The reaction sequence is applicable to even very weakly basic and sterically hindered amines, and the products are uncontaminated by over-alkylation. In addition, the transition-metal-catalysed j V-monoalkylation of amines by alcohols has been previously reported (c/. Vol. 6, p. 198) as a method to overcome problems associated with over-alkylation. A similar procedure for the preparation of unsymmetrical secondary (and tertiary) amines utilises a ruthenium catalyst, and is particularly suitable for the synthesis of cyclic amines. ... [Pg.204]

The use of palladium and ruthenium as halogen-free carbonylation catalysts has been studied intensively by Shell. The catalysts were principally designed for the carbonylation of olefins in the presence of alcohols in order to yield carboxylic esters [26], but work also well for the synthesis of carboxylic acids or anhydrides. The latter are formed when the reaction is conducted in an acid as a solvent [27]. The palladium systems typically consist of palladium acetate, tertiary phosphines, and strong acids such as mineral acids or acids with weak or noncoordinating anions such as p-toluenesulfonic acid. Remarkable activities are achieved when aromatic phosphines that carry pyridines as substituents are... [Pg.140]


See other pages where Acetic anhydride ruthenium catalyst is mentioned: [Pg.998]    [Pg.444]    [Pg.165]    [Pg.766]    [Pg.427]    [Pg.239]    [Pg.896]    [Pg.1711]    [Pg.1390]    [Pg.54]    [Pg.427]    [Pg.202]    [Pg.3881]    [Pg.346]    [Pg.21]    [Pg.410]    [Pg.90]   
See also in sourсe #XX -- [ Pg.239 ]

See also in sourсe #XX -- [ Pg.8 , Pg.239 ]

See also in sourсe #XX -- [ Pg.8 , Pg.239 ]




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