Chlorine dioxide carbonyl compounds

Photolytic. Major products reported from the photooxidation of butane with nitrogen oxides under atmospheric conditions were acetaldehyde, formaldehyde, and 2-butanone. Minor products included peroxyacyl nitrates and methyl, ethyl and propyl nitrates, carbon monoxide, and carbon dioxide. Biacetyl, tert-butyl nitrate, ethanol, and acetone were reported as trace products (Altshuller, 1983 Bufalini et al, 1971). The amount of sec-butyl nitrate formed was about twice that of n-butyl nitrate. 2-Butanone was the major photooxidation product with a yield of 37% (Evmorfopoulos and Glavas, 1998). Irradiation of butane in the presence of chlorine yielded carbon monoxide, carbon dioxide, hydroperoxides, peroxyacid, and other carbonyl compounds (Hanst and Gay, 1983). Nitrous acid vapor and butane in a smog chamber were irradiated with UV light. Major oxidation products identified included 2-butanone, acetaldehyde, and butanal. Minor products included peroxyacetyl nitrate, methyl nitrate, and unidentified compounds (Cox et al., 1981). 

The Ponzio reaction provides a useful route to gem-dinitro compounds and involves treating oximes with a solution of nitrogen dioxide or its dimer in diethyl ether or a chlorinated solvent. The Ponzio reaction works best for aromatic oximes where the synthesis of many substituted aryldinitromethanes have been reported. Compound (56), an isomer of TNT, is formed from the reaction of dinitrogen tetroxide with the oxime of benzaldehyde (55) followed by mononitration of the aromatic ring with mixed acid. Yields are usually much lower for aliphatic aldoximes and ketoximes. " The parent carbonyl compound of the oxime is usually the major by-product in these reactions. 

In contrast to aliphatic alcohols, which are mostly less acidic than phenol, phenol forms salts with aqueous alkali hydroxide solutions. At room temperature, phenol can be liberated from the salts even with carbon dioxide. At temperatures near the boiling point of phenol, it can displace carboxylic acids, e.g. acetic acid, from their salts, and then phenolates are formed. The contribution of ortho- and -quinonoid resonance structures allows electrophilic substitution reactions such as chlorination, sulphonation, nitration, nitrosation and mercuration. The introduction of two or three nitro groups into the benzene ring can only be achieved indirectly because of the sensitivity of phenol towards oxidation. Nitrosation in the para position can be carried out even at ice bath temperature. Phenol readily reacts with carbonyl compounds in the presence of acid or basic catalysts. Formaldehyde reacts with phenol to yield hydroxybenzyl alcohols, and synthetic resins on further reaction. Reaction of acetone with phenol yields bisphenol A [2,2-bis(4-hydroxyphenyl)propane]. 

Phosgene can be prepared from carbon monoxide, from halogenated hydrocarbons, from carbonaceous materials, from carbon dioxide, carbonyl sulfide or carbon disulfide, and from other oxygenated compounds [39]. The method based on the chlorination of carbon monoxide is by far the most important and has been scaled-up for the commercial manufacture of phosgene. 

Chlorine can also combine directly with certain compounds, such as the addition to sulphur dioxide and to carbon monoxide to form sulphuryl chloride and carbonyl chloride (phosgene) respectively. The latter has wide application as a war gas. 

Halomethyl compounds are subdivided into monohalomethyls, which are alkylating agents, and polyhalomethyls, which must be metabolized to an ultimate species. Reductive dechlorination of carbon tetrachloride 353) to chloroform by rabbit liver microsomes parallels the concentration of cytochrome P-450 in the microsomes but requires anaerobic conditions and NADPH. The identification of hexachloroethane after incubation of NADPH-reduced microsomes with carbon tetrachloride is indicative of homolytic formation of the free radicals of chlorine and trichloromethyl and supports the hypothesis that such species initiate an autocatalytic peroxidation of lipid membranes that results in the observed hepatotoxicity. A similar scheme for radical formation and lipid destruction has been described by Reynolds and Moslen for halothane. In contrast to the reductive dechlorination of carbon tetrachloride, the metabolism of chloroform to carbon dioxide in vitro requires oxygen and produces carbonyl chloride (phosgene) as an intermediate. That this also... 

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