1- -5-chlor- -3-oxid

Rather high (80-90%) yields of dihydrodiazepines are observed when the reaction is carried out on a MgO surface in the presence of phosphorus chlor-oxide [17]. In this manner some dihydrobezodiazepine derivatives 78 and 80 with alkyl substituents are obtained (Scheme 4.25). It should be noted that high product yields are also observed in the reactions of o-PDA with cyclic ketones (e.g., cyclopentanone, cyclohexanone and cycloheptanone), which is not typical of routine acid catalysis [14, 99]. 

Photochromic anthrapyridones (IIB1, IIB2) were produced by cyclization of 1-chloracetylamino-4-(or -5)-phenoxyanthraquinones with the subsequent reductive elimination of the pyridine group from the products obtained in pyridine (Scheme 2).38 Photochromic chloro derivatives of pyridines (IIC) were synthesized by the interaction of the resultant photochromic anthrapyridines with phosphorous chlor-oxide.38... 

Manganese(IV) oxide is a dark-brown solid, insoluble in water and dilute acids. Its catalytic decomposition of potassium chlor-ate(V) and hydrogen peroxide has already been mentioned. It dissolves slowly in alkalis to form manganates(lW), but the constitution of these is uncertain. It dissolves in ice-cold concentrated hydrochloric acid forming the complex octahedral hexachloromangan-ate(IV) ion ... 

Commercial metal anodes for the chlorine industry came about after the late 1960s when a series of worldwide patents were awarded (6—8). These were based not on the use of the platinum-group metals (qv) themselves, but on coatings comprised of platinum-group metal oxides or a mixture of these oxides with valve metal oxides, such as titanium oxide (see Platinum-GROUP metals, compounds Titanium compounds). In the case of chlor-alkaH production, the platinum-group metal oxides that proved most appropriate for use as coatings on anodes were those of mthenium and iridium. 

Alternatives to oxychlorination have also been proposed as part of a balanced VCM plant. In the past, many vinyl chloride manufacturers used a balanced ethylene—acetylene process for a brief period prior to the commercialization of oxychlorination technology. Addition of HCl to acetylene was used instead of ethylene oxychlorination to consume the HCl made in EDC pyrolysis. Since the 1950s, the relative costs of ethylene and acetylene have made this route economically unattractive. Another alternative is HCl oxidation to chlorine, which can subsequently be used in dkect chlorination (131). The SheU-Deacon (132), Kel-Chlor (133), and MT-Chlor (134) processes, as well as a process recently developed at the University of Southern California (135) are among the available commercial HCl oxidation technologies. Each has had very limited industrial appHcation, perhaps because the equiHbrium reaction is incomplete and the mixture of HCl, O2, CI2, and water presents very challenging separation, purification, and handling requkements. HCl oxidation does not compare favorably with oxychlorination because it also requkes twice the dkect chlorination capacity for a balanced vinyl chloride plant. Consequently, it is doubtful that it will ever displace oxychlorination in the production of vinyl chloride by the balanced ethylene process. 

There have been a number of cell designs tested for this reaction. Undivided cells using sodium bromide electrolyte have been tried (see, for example. Ref. 29). These have had electrode shapes for in-ceU propylene absorption into the electrolyte. The chief advantages of the electrochemical route to propylene oxide are elimination of the need for chlorine and lime, as well as avoidance of calcium chloride disposal (see Calcium compounds, calcium CHLORIDE Lime and limestone). An indirect electrochemical approach meeting these same objectives employs the chlorine produced at the anode of a membrane cell for preparing the propylene chlorohydrin external to the electrolysis system. The caustic made at the cathode is used to convert the chlorohydrin to propylene oxide, reforming a NaCl solution which is recycled. Attractive economics are claimed for this combined chlor-alkali electrolysis and propylene oxide manufacture (135). 

Chlor-oxyd, n. chlorine oxide, -phosphor, m. phosphorus chloride, -pikrin, n. chloropicrin. -platin, n. platinic chloride, -platinsiiure,. chloroplatinic acid, -quecksilber, n. mercury chloride (either one), -raucherung, /. chlorine fumigation. 

Chlor-siure, /. chloric acid. -sMureanhydrid, n. chloric anhydride, chlorine(V) oxide, -schwefel, n. sulfur chloride (esp. the monochloride). -silber, n. silver chloride, -sili-cium, n. silicon tetrachloride, -soda, /. = Chlornatron. -stickstoff, m. nitrogen chloride. -Strom, m. stream of chlorine, -strontium, n. strontium chloride, -suifonsaure, /. chlorosulfonic acid, chlorosulfuric acid, -toluol, n. chlorotoluene. -fibertrager, m. chlorine carrier. 

Oxy-aldehyd, n, hydroxy aldehyde, -ammo-niak, n, oxyammonia (hydroxylamine), -azoverbindung, /. hydroxyazo compound, -benzol, n, hydroxybenzene (phenol), -bem-steinsaure. /, hydroxysuccinic acid (malic acid). -biazol, n. oxadiazole, oxdiazole. -bitumen, n, oxidized bitumen, -carbon-s ure, /, hydroxycarboxylic acid, -chlnoltn, n. hydroxyquinoline, -clunon, n. hydroxy-quinone. -chlorid, n. oxychloride, -chlor-kupfer, n. copper oxychloride, -cyan, n. oxycyanogen. 

Staono-. stannous, stanno-, tin(II). -azetat, n. stannous acetate, tin(II) acetate, -chlorid, n. stannous chloride, tin(II) chloride, -chlor-wasserstoffsMure, /. chlorostannous acid, -hydroxyd, n. stannous hydroxide, tin(II) hydroxide. -jodid, n. stannous iodide, tin(II) iodide. -jodwasserstoffsaure, /. iodostannous acid, -oxyd, n. stannous oxide, tin(II) oxide, -salz, n. stannous salt, tin(II) salt, -sulfid, n. stannous sulfide, tin(II) sulfide. -verbindung, /, stannous compoimd, tin(II) compound,... 

N 24.12% brick red solid mp, decomps when heated over 300°. Insol in w and the usual organic solvents as well as weak acids and alkalies. Comm prepn (Ref 3) is from thiocyanic acid and/or thiocyanates either by anodic oxidation or by interaction with hydrogen peroxide or halogens. The yield is impure because it contains both H and O. The S content varies between 45 and 55%. Lab prepn of the pure polymer is by reacting the Na salt of 5-chlor-3-mercapto 1,2,4-thiodiazols with either acet, ethanol or w (Refs 1 2)... 

Chlor-2-methyl- 502 4-Chlor-2-methyl- -1-oxid 502 2-Chlor-5-nitro- 686 Cyan -88, 119... 

Chlor-2,4-diamino- -1-oxid 502 6-Chlor-4-dichlormethyl-2-phenyl- 618 6-Chlor-4-mcthoxy-2-phenyl- 595 6-Chlor-4-methyl-2-phcnyl- 595 6-Chlor-4-trichlormethyl-2-phenyl- 618... 

Chlor-phenyl)- 693 2-(4-Chlor-phenyl)- -1-oxid 693 2-(2-Hydroxy-4-methyl-phenyl)- 693 2-(2-Hydroxy-5-methyl-phenyl)- -1-oxid 693 2-(4-Methoxy-phenyl)- 693 2-(4-Methoxy-phenyl)- -1-oxid 693... 

Hydrodimerisierung 651 2-Amino-4-methyl- 502 2-Amino-4-methyl- -1-oxid 502 4-Chlor- 620 1,2-Dihydro- 87... 

This iron-ate complex 19 is also able to catalyze the reduction of 4-nitroanisole to 4-methoxyaniline or Ullmann-type biaryl couplings of bis(2-bromophenyl) methylamines 31 at room temperature. In contrast, the corresponding bis(2-chlor-ophenyl)methylamines proved to be unreactive under these conditions. A shift to the dianion-type electron transfer(ET)-reagent [Me4Fe]Li2 afforded the biaryl as well with the dichloro substrates at room temperature, while the dibromo substrates proved to be reactive even at —78°C under these reaction conditions. This effect is attributed to the more negative oxidation potential of dianion-type [Me4Fe]Li2. 

The starting material for all industrial chlorine chemistry is sodium chloride, obtained primarily by evaporation of seawater. The chloride ion is highly stable and must be oxidized electrolytically to produce chlorine gas. This is carried out on an industrial scale using the chlor-alkali process, which is shown schematically in Figure 21-15. The electrochemistry involved in the chlor-alkali process is discussed in Section 19-. As with all electrolytic processes, the energy costs are very high, but the process is economically feasible because it generates three commercially valuable products H2 gas, aqueous NaOH, and CI2 gas. 

When chlor-alkali electrolysis is conducted in an undivided cell with mild-steel cathode, the chlorine generated anodically will react with the alkali produced cathodically, and a solution of sodium hypochlorite NaClO is formed. Hypochlorite ions are readily oxidized at the anode to chlorate ions this is the basis for electrolytic chlorate production. Perchlorates can also be obtained electrochemically. 

Aniline-based amino-squaraines 40 can be obtained via reduction of oxo-squar-aines with NaBFLj in methanol followed by substitution and oxidation with chlor-anil or lead dioxide [106] (Fig. 11). 

HOCl-mediated protein oxidation accelerates under pathophysiological conditions. Thus, proteins from extracellular matrix obtained from advanced human atherosclerotic lesions contained the enhanced levels of oxidized amino acids (DOPA and dityrosine) compared to healthy arterial tissue [44], It was also found that superoxide enhanced the prooxidant effect of hypochlorite in protein oxidation supposedly by the decomposition of chloramines and chlor-amides forming nitrogen-centered free radicals and increasing protein fragmentation [45], In addition to chlorination, hypochlorite is able to oxidize proteins. The most readily oxidized amino acid residue of protein is methionine. Methionine is reversibly oxidized by many oxidants including hypochlorite to methionine sulfide and irreversibly to methionine sulfone [46] ... 

Kel-Chlor [Kellogg Chlorine] A non-catalytic version of the Deacon process for making chlorine by oxidizing hydrochloric acid, in which nitrosyl sulfuric acid and nitrosyl chloride are intermediates and concentrated sulfuric acid is used as a dehydrating agent ... 

Enthalt die Zusammensetzung Metall-Elemente, z. B. Natrium- Oder Kalium-Nitrat, Erdalkali- Oder Blei-Salze, so rechnet man (wiederum konventionell) alle Alkali-Anteile auf ihre Karbonate als Explosions-produkt, bei alien anderen Metallen nimmt man ihre Oxide als Reak-tionsprodukt an enthalt der Explosivstoff Chlor, so wird auf Chloride bzw. Chlorwasserstoff, bei Schwefel auf S02 gerechnet. 

Several chlor-alkali producers have some control over surplus caustic inasmuch as they use large quantities in-house. In some cases, if caustic is tight then the weak cell liquor can be upgraded and placed on the market. Dow s propylene oxide (PO)... 

Physical separation of the chlor-alkali/EDC plant from the cracking/oxyhydro-chlorination plant does create some complications regarding the necessary duplication of feedstocks and services. In particular, there will be the need for two ethylene supplies and for two independent thermal oxidation systems. Approximately half of the total ethylene must be provided as the feed to the EDC unit with the remainder fed to the oxyhydrochlorination unit. The EDC unit as well as the cracking and oxyhydrochlorination units will generate off-gases that require emission control,... 

The oxidation of alcohols to carbonyl compounds has been studied by several authors and a variety of methods have been used. Papers concerned vith such oxidations are illustrated (Scheme 3.26). Good results have been obtained using pyridinium chlor-ochromate (PCC) adsorbed onto silica gel for the selective oxidation of unsaturated substrates e.g. terpene [135] and furanyl derivatives [136]. Steroidal homoallylic alcohols can be converted to the corresponding 4-ene-3,6-diones using tetrapropylammo-nium per-ruthenate (TPAP) in catalytic amounts [137]. In this case, the oxidising agent is N-methyl morpholine N-oxide (NMO). 

The current state-of-the-art proton exchange membrane is Nafion, a DuPont product that was developed in the late 1960s primarily as a permselective separator in chlor-alkali electrolyzers. Nation s poly(perfluorosulfonic acid) structure imparts exceptional oxidative and chemical stability, which is also important in fuel cell applications. 

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