Dioxide 383 preparation

Benzothiadiazole 1,1-dioxide can be conveniently assayed and characterized without isolation by forming its adduct with cyclopentadiene.5 The following procedure illustrates characterization, for assay the same procedure can be applied to an aliquot, with all amounts scaled down in proportion. The dried ether extract of 1,2,3-benzothiadiazole 1,1-dioxide prepared from 1.43 g (0.0080 mole) of sodium 2-aminobenzene-sulfinate is concentrated to about 20 ml at 0°, and 20 ml. of acetonitrile at —20° is added. Twenty milliliters of cold, freshly prepared cyclopentadiene6 is added The mixture is kept overnight at —10° to 0°. Solvent and excess cyclopentadiene are removed by evaporation at 0° under reduced pressure to leave 1.20-1.28 g. (64-68% based on sodium 2-aminobenzenesulfinate) of crude 1-1 adduct, mp. 87° (dec.). For purification it is dissolved in 20 ml. of methylene chloride, 70 ml. of ether is added, and the solution is kept at —70°. Adduct decomposing at 90° crystallizes recovery is about 75%. From pure, crystalline 1, 2, 3-benzothiadiazole 1,1-dioxide the yield of adduct is 92-98%. 

T. Johnson and R. Paul, "NAAQS Exposure Model (NEM) and Its Application to Nitrogen Dioxide." Prepared for the U.S. Environmental Protection Agency OAQPS, 1981. 

Mixtures with mercury (II) oxide and manganese dioxide prepared at — 80°C ignited at 20° and reacted violently at 15°C, respectively. Copper(II) oxide reacted vigorously at 25 °C without ignition. 

Another class of chain scission positive resists is the poly(olefin-sulfones). These materials are alternating copolymers of an olefin and sulfur dioxide, prepared by free radical solution polymerization. The relatively weak C-S bond, 60 kcal/mole compared with 80 kcal/mole for a carbon-carbon bond, is readily cleaved upon irradiation (Gs values for these polymers are typically 10), and several sensitive resists have been developed based on this chemistry (53). One material that has been made commercially available is poly (butene-1-sulfone) (54). 

Grignard reagents have reacted with diimide dioxides prepared from nitrosohydroxylamines and with toluenesulfonyl derivatives of nitroso-hydroxylamines to prepare unsymmetrical azoxy compounds, including aliphatic-aromatic types. 

The oxidation can also be effected in the wet way by the use of nitric acid. The crude dioxide prepared in this way can be purified by sublimation.7... 

Nitrogen pentoxide can be made by dehydration of anhydrous nitric acid with phosphorus pentoxide and sublimation from the mixture at about 40°. Resublimation with ozone and more phosphorus pentoxide gives pure white crystals which rattle around in the reaction chamber after slight evacuation. Direct oxidation with ozone of nitrogen dioxide prepared by heating lead nitrate is a somewhat better way of making the material. 

Chlorine dioxide, prepared from sodium chlorate by reduction, reacts quite selectively with lignin and is therefore widely used for pulp bleaching. At slightly acidic conditions (pH 4-5) chlorine dioxide can be reduced to chloride ions ... 

Thermostat bath with a heater, adjustable thermoregulator, and stirrer thermometer with a resolution of at least 0.01 K (a platinum resistance thermometer, thermocouple or quartz thermometer could be used see Chapter XVII) illuminating light and cathetometer for reading the vertical position of the menisci number of sealed capillaries of uniform bore containing varying amounts of carbon dioxide, prepared in advance. 

Similar behavior has been observed with different modifications of Mn(IV) oxides. The cryptomelane type of hydrous manganese dioxide prepared by the reaction of Mn(II) and KMn04 in sulfuric acid solution exhibits an extremely high selectivity for potassium ions [120]. The spinel type of manganese oxide prepared by the introduction of lithium ion has exhibited an extremely high selectivity for lithium ion [121, 122]. These aspects are considered later. 

Suzuki A, Tukuda R (1969) Kinetics of the transition of titanium dioxide prepared by sulfate process and chloride process. Bull Chem Soc Japan 42 1853-1957... 

Waitkins, G. R., Clark, C. W. Selenium dioxide preparation, properties, and use as oxidizing agent. Chem. Rev. 1945, 36, 235-289. Rabjohn, N. Selenium dioxide oxidation. Org. React. 1949, 5, 331-386. 

Konig et aV found the preparation of the highly sensitive diphenoquinone by oxidation of 4,4 -dihydroxydiphenyl with lead dioxide unsatisfactory, even when the active lead dioxide prepared according to Kuhn and Hammer by hydrolysis of lead tetraacetate was used. However, they found that the oxidation can be accomplished very satisfactorily with lead tetraacetate itself. A solution of 7.14 g. of lead tetraacetate in 140 g. of anhydrous acetic acid is added at 30° to a solution of 2 g. 

Furthermore, according to the publication, pesticide activity can be inferred for some thiadiazoline 1,1-dioxides prepared by authors in the Soviet Union (75M11). 

Eremenko, B.V. et al., Stability of aqueous dispersions of the hydrated titanium dioxide prepared by titanium tetrachloride hydrolysis, Colloid J., 63, 173, 2001. 

Randon, J. et al.. Interfacial properties of zirconium dioxide prepared by the sol-gel process. Colloids Surf, 52, 241, 1991. 

Moneghini M, Kikic I, Voinovich D, Perissutti B, Filipovic-Grcic J. Processing of carbamazepine-PEG 4000 solid dispersions with supercritical carbon dioxide preparation, characterization, and in vitro dissolution. Int J Pharm 2001 222 129-138. 

Oxidation of allylic or benzylic alcohols. Manganese dioxide prepared by ozoniza-tion of manganese (II) nitrate is an effective agent for oxidation of allylic and benzylic alcohols.38... 

Oxidation of nitrogen compounds [bottom of 1, 640], Bhatnagar and George2011 found that chalcone phenylhydrazones are oxidized to pyrazoles in good yield by active manganese dioxide prepared according to Pratt and McGovern.19 Benzala-... 

Perbenzoic acid is the oxidizing reagent that was used at the earliest stage of the chemistry of thiophene 1,1-dioxides. The thiophene 1,1-dioxides prepared by this oxidation are summarized in Table 1 [3-6]. Yields are also shown for convenience from a synthetic point of view throughout this review, if they were given in the literature. 

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