Manganese carboxylates

Studies devoted to create high-density molecular memory devices (ideally, it is hoped to find materials in which each bit of digital information might be stored on a single molecule) are very active89 and larger manganese-carboxylate assemblies have been obtained (up to... 

Lis, T., Preparation, structure, and magnetic-properties of a dodecanuclear mixed-valence manganese carboxylate. Acta Crystallogr Sect. B-Struct. Commun. 1980, 36, 2042-2046. 

Christou, G. Manganese carboxylate chemistry and its biological relevance. Acc. Chem. Res. 22... 

Commercial poly(butadiene), which is mainly the 1,4 isomer, is also used to improve the impact resistance of polystyrene (Chapter 1). Polydienes also increase the rate of physical disintegration of polyblend containing them. The addition of a styrene-butadiene block copolymer e.g. SBS, page 9 et seq.) to polyethylene also accelerates the peroxidation of the latter. However, this system also requires a polymer-soluble transition metal ion catalyst e.g. an iron or manganese carboxylate) to increase the rate of photooxidation in the environment by the reactions shown in Scheme 5.3. The products formed by breakdown of alkoxyl radicals (PO ) (Scheme 3.4) are then rapidly biodegradable in compost (page 107 et seq.). 

The oxidation of cyclohexene in the presence of copper, cobalt and manganese carboxylates has continued to receive attention in recent years [430-441]. The stable monomeric products of reaction are largely 2-cyclohexene-l-one and 2-cyclo-hexene-l-ol with smaller amounts of cyclohexene oxide. Cyclohexenyl hydroperoxide formed by attack of dioxygen on the allylic radical produced by allylic-hydrogen abstraction, has been established to be the reaction intermediate. The product profile has been found to vary somewhat with the metal complex used. It was found [431] that with Co(II) or Mn(II) carboxylates reaction rate and selectivity to 2-cyclohexene-l-one were maximal at 46 °C. 

The use of cobalt and manganese carboxylates to initiate the oxidation of a large number of olefins such as the butenes [447, 448], propylene [449], oleic [450] linoleic [451], and stearic [452, 453] acids or their derivatives and a-methylstyrene [454, 455] is well known. The kinetics of oxidation of a-methylstyrene in the presence of cobaltous and manganous acetylacetonates as well as copper phthalocy-anine have been investigated [454, 455]. The results of this study led Kamiya to postulate a mechanism involving formation of radical species by a metal dioxygen complex, equation (270), concurrent with radical generation by hydroperoxide decomposition. 

Potassium permanganate (KMn04) will also oxidize pri mary alcohols to carboxylic acids What is the oxidation state of manganese in KMn04 ... 

Most commercial sorbic acid is produced by a modification of this route. Catalysts composed of metals (2inc, cadmium, nickel, copper, manganese, and cobalt), metal oxides, or carboxylate salts of bivalent transition metals (2inc isovalerate) produce a condensation adduct with ketene and crotonaldehyde (22—24), which has been identified as (5). 

Alkyds. Alkyd resins (qv) are polyesters formed by the reaction of polybasic acids, unsaturated fatty acids, and polyhydric alcohols (see Alcohols, POLYHYDRic). Modified alkyds are made when epoxy, sUicone, urethane, or vinyl resins take part in this reaction. The resins cross-link by reaction with oxygen in the air, and carboxylate salts of cobalt, chromium, manganese, zinc, or zirconium are included in the formulation to catalyze drying. 

Nickel peroxide is a solid, insoluble oxidant prepared by reaction of nickel (II) salts with hypochlorite or ozone in aqueous alkaline solution. This reagent when used in nonpolar medium is similar to, but more reactive than, activated manganese dioxide in selectively oxidizing allylic or acetylenic alcohols. It also reacts rapidly with amines, phenols, hydrazones and sulfides so that selective oxidation of allylic alcohols in the presence of these functionalities may not be possible. In basic media the oxidizing power of nickel peroxide is increased and saturated primary alcohols can be oxidized directly to carboxylic acids. In the presence of ammonia at —20°, primary allylic alcohols give amides while at elevated temperatures nitriles are formed. At elevated temperatures efficient cleavage of a-glycols, a-ketols... 

The present synthesis10 consists of two simple steps, uses readily available and inexpensive starting materials, and produces pure material in high overall yield. It is based on two observations that nonenolizable ketones may be cleaved to carboxylic acids by potassium ferf-butoxide-water,2 and that aryl 2 chlorophenyl ketones may be cleaved with loss of the 2-chlorophenyl group to give only one of the two possible acids.11 Other compounds prepared by this route include carboxycyclopentadienyltriearbonylmanganese [Manganese, tricar-bonyl[(l, 2,3,4,5- )-l-carboxy-2,4-cyclopentadien-l-yl]-] (79%)10 and... 

The paraffin wax is oxidized by air in a liquid phase process at 110-130°C. Catalysts for this radical reaction are cobalt or manganese salts [54]. The quality of the obtained mixture of homologous carboxylic acids is impaired by numerous byproducts such as aldehydes, ketones, lactones, esters, dicarboxylic acids, and other compounds. These are formed despite a partial conversion of the paraffin and necessitate an expensive workup of the reaction product [50,55]. 

The aerobic and anaerobic degradation of acetone is initiated by carboxylation to acetoac-etate. The involvement of manganese has been examined in photoheterotrophically grown Rhodobacter capsulatus strain BIO and the presence of Mn verified from the X-band EPR spectrum (Boyd et al. 2004). 

Amoco Amoco Chemicals Company, a subsidiary of Amoco Corporation, formerly Standard Oil Company (IN), is best known in the chemicals industry for its modification of the Mid-Century process for making pure terephthalic acid. /7-Xylene in acetic acid solution is oxidized with air at high temperature and pressure. Small amounts of manganese, cobalt, and bromide are used as catalysts. The modification allows the use of terephthalic acid, rather than dimethyl terephthalate, for making fiber. The process can also be used for oxidizing other methylbenzenes and methylnaphthalenes to aromatic carboxylic acids. See also Maruzen. 

Manganese, Mn2+ (d5) 6, octahedral O-Carboxylate, phosphate, AMmidazole Structure in oxidases, photosynthesis... 

Aldehyde 244 reacts with manganese dioxide and sodium cyanide in ethanol to give ethyl ester 245 (Scheme 19), while oxidation of alcohol 12 with sodium peroxodisulfate in the presence of a catalytic amount of ruthenium chloride furnishes the carboxylic acid 246 (Scheme 19) <1998CPB287>. 

Chemical manganese dioxide (CMD). This form of Mn02 is used for batteries it is available from I. C. Sample office (Cleveland, Ohio, 44101). Shioiri et al. report it is superior to commercial activated Mn02 (Aldrich) and more convenient than freshly prepared activated Mn02 for dehydrogenation of 2-(l-ami-noalkyl)thiazolidine-4-carboxylic acids to the corresponding thiazoles (thiazole amino acids). 

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