Tetraoxane

PEROXIDES AND PEROXIDE COMPOUNDS - ORGANIC PEROXIDES] (Vol 18) 1,3,5,7-Tetraoxane [293-30-1]... 

A practical synthesis has been claimed for the cycHc tetramer of formaldehyde, 1,3,5,7-tetraoxane [293-30-17, which has a boiling point of 175°C and a melting point of 112°C (155). It has found some use in textde treatment in Japan. 

We have recently shown that solid state polymerizations can also be carried out via plasma initiation ( ). In that work, 1, 3,5-trloxane and 1,3,5,7-tetraoxane were used as monomer crystals. Highly crystalline polyoxymethylene were obtained using either monomer. However, if the monomers were dissolved in an appropriate solvent, such as cyclohexane, then no polymer was formed with plasma initiation. These observations are the reverse of those for AM and MAM, where plasma initiated polymerizations in solution appear to proceed satisfactorily during homogeneous post-polymerization periods, but not in the bulk crystalline state. The unresolved question is then if water molecules may have dissociated in the plasma in highly active radical species, perhaps OH or H, to promote efficient initiation. 

Formation of polymerizable by-products (formaldehyde, 1,3,5,7-tetraoxane, 1,3,5,7,9-pentaoxane, and other cycles). 

Valuable information on the mechanism of the process and on the confirmation of the formulated assumptions was obtained by analyzing the low-molecular-weight by-products of trioxane polymerization reaction 1,3,5,7-tetraoxane and formaldehyde. Theoretical analysis has shown that, depending on the state of active centers (surface or dissolved) and the length of the dissolved portion of the polymer chain, the steady-state concentration of 1,3,5,7-tetraoxane and formaldehyde changes. A comparison between experimental and theoretical data has shown that at monomer... 

Formaldehyde, trioxane, 1,3,5,7-tetraoxane, and dissolved oligomer chains (with a small degree of polymerization) are here in equilibrium. Therefore, the steady-state concentrations of formaldehyde and 1,3,5,7-tetraoxane depend on trioxane concen-... 

One of the objectives of the investigators during their research into the thermodynamic characteristics of the formaldehyde — trioxane — 1,3,5,7-tetraoxane — —... 

Several papers57"59 were devoted to investigating a complex process such as the cationic copolymerization of monomeric formaldehyde with dioxolane in the gas, liquid, and gas-liquid phases. It is known that polyacetal resins are industrially produced by copolymerizing cyclic acetals (trioxane, 1,3,5,7-tetraoxane), or by anionic homopolymerization of monomeric formaldehyde with subsequent modification of end groups. 

Trioxane and Tetraoxane. The cycHc symmetrical trimer of formaldehyde, trioxane [110-88-3] is prepared by acid-catalyzed Hquid- or vapor-phase processes (147—151). It is a colorless crystalline soHd that bods at 114.5°C and melts at 61—62°C (17,152). The heats of formation are — 176.9 kJ/mol (—42.28 kcal/mol) from monomeric formaldehyde and —88.7 kJ/mol (—21.19 kcal/mol) from 60% aqueous formaldehyde. It can be produced by continuous distillation of 60% aqueous formaldehyde containing 2—5% sulfuric acid. Trioxane is extracted from the distillate with benzene or methylene chloride and recovered by distillation (153) or crystallization (154). It is mainly used for the production of acetal resins (qv). 

Oxidative processes can also be used to prepare DMF. For example, it can be produced from tetraoxane (a source of formaldehyde (qv)), oxygen, and dimethylamine over Pd—AI2O2 (24) or from trimethylamine and oxygen ia the presence of a metal haUde catalyst (25). 

See 3,6-Diethyl-3,6-dimethyl-l,2,4,5-tetraoxane See other cyclic peroxides... 

The crude products of ozonolysis at — 30°C of the chloroalkene tended to decompose explosively on warming to ambient temperature, particularly in absence of solvents. The products included the individually explosive compounds acetyl 1,1,-dichloroethyl peroxide, 3,6-dichloro-3,6-dimethyl-2,3,5,6-tetraoxane and diacetyl peroxide [1], Ozonolysis in ethyl formate saturated with hydrogen chloride gives a high yield of 1,1-dichloroethyl hydroperoxide as a further unstable intermediate product [2],... 

Studies on the mode of activity of the antimalarials related to artemisinin have centred on simpler 1,2,4-trioxanes, 1,2,4,5-tetraoxanes and bicyclic endoperoxides <00H(52)1345 00JCS(P1)1265 00JMC2753 00TL3145>. The chemical and electro-chemical reduction of artemisinin has been reported <00JCS(P1)4279>. 

Minato, K., Yasuda, R. and Yano, H. (1990b). Improvement of dimensional stabihty and acoustic properties of wood for musical instruments with cyclic oxymethylenes. n. Formalization with tetraoxane. Mokuzai Gakkaishi, 36(11), 990-996. 

Treatment of variously substituted cyclohexanones with H2O2 in acidic medium leads to formation of dispiro-l,2,4,5-tetraoxanes (16, Section II.A.2.a). The products obtained in the case of 16a and 16b are mixtures of the meso, D- and L-stereoisomers, whereas 16c is a single compound. See also Scheme 7 for the formation of cis- and trans-3,6-dichloro-l,2,4,5-tetraoxanes, obtained on ozonolysis of 1,2-dichloroethylene " . 

As noted in the previous section, Vennerstrom and coworkers have carried out a large amount of research into the synthesis of tetraoxanes, e.g. 72, 73a and 73b, some of which have proven to be highly potent in For the synthesis of symmetrical... 

Antimalarial activity is also shown by 13,43-tetraoxanes and these compounds have been synthesised by the acid-catalysed dimerisation of ozonides <99JMC2604>. Ozonolysis of vinyl ethers and cyclocondensation of the derived bis(hydroperoxides) with carbonyl... 

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