Acetate manganese

Oxidation. Acetaldehyde is readily oxidised with oxygen or air to acetic acid, acetic anhydride, and peracetic acid (see Acetic acid and derivatives). The principal product depends on the reaction conditions. Acetic acid [64-19-7] may be produced commercially by the Hquid-phase oxidation of acetaldehyde at 65°C using cobalt or manganese acetate dissolved in acetic acid as a catalyst (34). Liquid-phase oxidation in the presence of mixed acetates of copper and cobalt yields acetic anhydride [108-24-7] (35). Peroxyacetic acid or a perester is beheved to be the precursor in both syntheses. There are two commercial processes for the production of peracetic acid [79-21 -0]. Low temperature oxidation of acetaldehyde in the presence of metal salts, ultraviolet irradiation, or osone yields acetaldehyde monoperacetate, which can be decomposed to peracetic acid and acetaldehyde (36). Peracetic acid can also be formed directiy by Hquid-phase oxidation at 5—50°C with a cobalt salt catalyst (37) (see Peroxides and peroxy compounds). Nitric acid oxidation of acetaldehyde yields glyoxal [107-22-2] (38,39). Oxidations of /)-xylene to terephthaHc acid [100-21-0] and of ethanol to acetic acid are activated by acetaldehyde (40,41). 

Although an inherently more efficient process, the direct chemical oxidation of 3-methylpyridine does not have the same commercial significance as the oxidation of 2-methyl-5-ethylpyridine. Liquid-phase oxidation procedures are typically used (5). A Japanese patent describes a procedure that uses no solvent and avoids the use of acetic acid (6). In this procedure, 3-methylpyridine is combined with cobalt acetate, manganese acetate and aqueous hydrobromic acid in an autoclave. The mixture is pressurized to 101.3 kPa (100 atm) with air and allowed to react at 210°C. At a 32% conversion of the picoline, 19% of the acid was obtained. Electrochemical methods have also been described (7). 

On the other hand, the catalytic oxidation of a n-butane, using either cobalt or manganese acetate, produces acetic acid at 75-80% yield. Byproducts of commercial value are obtained in variable amounts. In the Celanese process, the oxidation reaction is performed at a temperature range of 150-225°C and a pressure of approximately 55 atmospheres. ... 

The main by-products are formic acid, ethanol, methanol, acetaldehyde, acetone, and methylethyl ketone (MEK). When manganese acetate is used as a catalyst, more formic acid (=25%) is obtained at the expense of acetic acid. 

Light naphtha containing hydrocarbons in the C5-C7 range is the preferred feedstock in Europe for producing acetic acid by oxidation. Similar to the catalytic oxidation of n-butane, the oxidation of light naphtha is performed at approximately the same temperature and pressure ranges (170-200°C and =50 atmospheres) in the presence of manganese acetate catalyst. The yield of acetic acid is approximately 40 wt%. 

The reaction occurs in the liquid phase at approximately 65 °C using manganese acetate as a catalyst. Uses of acetic acid have been noted in Chapter 5. 

Liquid-phase oxidation of o-xylene also works at approximately 150°C. Cobalt or manganese acetate in acetic acid medium serves as a catalyst. 

Butyraldehyde is oxidized to butyric acid in the presence of air using manganese acetate as catalyst [9, 10],... 

Synthesis. Porphyrazines Mg[pz(A4)], A = S203 crown, 81a, and Mg[pz(A4)], A = S204 crown, 81e, (35%) were prepared by cyclizing the appropriate crown dinitrile 80. Compounds 81a and 81e were demetalated with trifluoroacetic acid and remetalated with either copper or manganese acetate to form compounds 81b-81d and 81f-81h (Scheme 16) (25-27). 

Subsequent reaction of porphyrazines 170 and 171 with Cu(OAc)2 resulted in the selective metalation within the macrocyclic cavity to provide the corresponding copper complexes 166 (62%) and 172 (47%). Treatment of pz 170 with manganese acetate and iron sulfate in dimethyl sulfate gave the dmso adducts 173 (70%) and 174 (85%), respectively (168). Axial ligation was also observed when other metals were incorporated such as cobalt acetate, nickel acetate, and zinc acetate to give the metal complexes 175 (83%), 176 (70%), and 177 (90%) as the hydrates. The axial ligand of... 

O. (R,R)-N,N -Bis(3,5-di-tert-butylsalicylidene)-1,2-cyclohexanediamino manga-nese(lll) chloride. A 2-L, three-necked, round-bottomed flask equipped with a mechanical overhead stirrer, reflux condenser, and a 500-mL addition funnel is charged with 67.2 g (0.27 mol 3 eq) of manganese acetate tetrahydrate (Mn(0Ac)2-4H20) and 500 mL of ethanol. Stirring is begun and the solution is heated... 

Manganese acetate tetrahydrate Acetic acid, manganese (2+ salt), tetrahydrate (8,9) (6156-78-1)... 

Ohsaka s group has extensively examined the electrochemical behavior of both chemically and electrochemically deposited Mn02, both as discrete NPs and as nanostructured interfacial materials [61,64—81]. We focus here on two of their studies that exemplify the electrocatalytic nature of these nanoscale materials. In the first effort, El-Deab and Ohsaka explored the electrocatalytic behavior of MnOOH nanorods that had been electrodeposited onto Pt electrodes by oxidation of Mn(II) in an aqueous solution of manganese acetate [76]. The nanorods had average diameters of 20 nm and aspect ratios of 45 (i.e. average lengths of 900 nm) and covered nearly... 

The TPA process. The technology involves the oxidation of p-xylene, as shown already in Figure 18—2. The reaction takes place in the liquid phase in an acetic acid solvent at 400°F and 200 psi, with a cobalt acetate/ manganese acetate catalyst and sodium bromide promoter. Excess air is present to ensure the p-xylene is fully oxidized and to minimize by-products. The reaction time is about one hour. Yields are 90—95% based on the amount of p-xylene that ends up as TPA. Solid TPA has only limited solubility in acetic acid, so happily the TPA crystals drop out of solution as they form. They are continuously removed by filtration of a slipstream from the bottom of the reactor. The crude TPA is purified by aqueous methanol extraction that gives 99 % pure flakes. 

In 1995, Perkin-Ehner introduced a new enzyme rTth-DNA polymerase with a dual activity. It can perform both RT and PCR in the presence of manganese acetate buffer, sense and antisense primers, and nucleotides. This protocol is easier to perform and reduces total in situ RT-PCR reaction time (46). 

The chemical oxidation of cis- or iranx-stilbene was also investigated (Vinogradov et al. 1976). The oxidant was cobalt or manganese acetate and, in separate experiments, thallium trifluoroac-etate. Acetic or triflnoroacetic acid was used as a solvent. The results of such chemical oxidation were considered from the geometrical standpoint of the recovered (nonreacted) part of the initial substrate and stereoisomeric composition of the products obtained. This allowed the desirable comparison of electrochemical and chemical reactions to be made. 

In order to shorten the reaction time, various heavy metal salts (zinc, lead, and manganese acetates) of weak organic acids, zinc or cobalt and tin chlorides are added to the reaction mixture [11]. For example, refluxing an uncatalyzed mixture of 3 moles of isobutyl alcohol and urea for 150 hr at 108°-126°C gives a 49% yield of the carbamate. Adding lead acetate or cobalt chloride to the same reaction lowers the reaction time to 75 hr, at which point an 88-92 % yield is obtained. In another example, ethylene glycol (1 mole) and urea (2 moles) are heated for 3 hr at 135°-155°C with Mn(OAc)2 to give a 78% yield of the diurethane [11]. The commercial production of butyl carbamate uses catalytic quantities of cupric acetate [12]. 

Generation of Carboxymethyl and Nitromethyl Radicals by Use of Manganese Acetate as Redox Catalyst... 

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