S-trioxane, 2,4,6-Trimethyl

RCRA WASTE NUMBER LT 82 TRIACETALDEHYDE (FRENCH) 2,4,6-TRIMETHYL-l,3,5-TRIOXAAN PUTCH) 2,4,6-TRIMETHYL-s-TRIOXANE 2,4,6-TRI vIETHYL- ,3,5-TRIOXANE s-TRIMETHYLTRIOXY-METHYLENE 2,4,6-TRIMETIL-l,3,5-TRIOSSANO (ITALIAN)... 

T rimethyl-1,3,5-trioxaan 2,4,6-Trimethyl-s-trioxane 2,4,6-Trimetil-1,3,5-triossano s-Trimethyltrioxymethylene 1,3,5-Trioxane,... 

Synonyms Acetaldehyde, trimer Elaldehyde Paraacetaldehyde Paracetaldehyde Paral PCHO 2,4,6-Trimethyl-1,3,5-trioxacyclohexane 2,4,6-Trimethyl-1,3,5-trioxane 2,4,6-Trimethyl-s-trioxane s-Trimethyltrioxymethylene Empirical C6H12O3... 

Saturated heterocyclic rings containing oxygen, nitrogen, or sulfur atoms also exist preferentially in stable, chair conformations resembling that of cyclohexane. Physical measurements, such as those of electron diffraction and dipole moments, have shown this conformation for p-dioxane, -s-trioxane, ° paraldehyde, s-trithiane, and 2,4,6-trimethyl-s-tri-... 

Paraldehyde (2,4,6-trimethyl-l, 3,5-trioxane) was claimed to behave in a similar way [582], An early German patent, published after Eckenroth s note [582], claimed that no reaction occurs between COClj and aldehydes at normal temperatures [612], and attempts to repeat Eckenroth s preparation [582] have not been successful [1763]. However, by combining the vapours of phosgene and ethanal at atmospheric pressure in a flow system over an activated charcoal catalyst, 1,1 -dichloroethane and carbon dioxide are found to be co-produced, especially in the temperature range of 150-200 "C [1753,ICI98,ICI99]. It was confirmed that no reaction occurs in the absence of a catalyst between 25 and 400 C [1763]. 

Using the rigid-rotor harmonic-oscillator approximation on the basis of molecular constants and the enthalpies of formation, the thermodynamic functions C°p, S°, — G° —H°o)/T, H° — H°o, and the properties of formation Af<7°, and log K°(to 1500 K in the ideal gas state at a pressure of 1 bar, were calculated at 298.15 K and are given in Table 9 <1992MI121, 1995MI1351>. Unfortunately, no experimental or theoretical data are available for comparison. From the equation log i = 30.25 - 3.38 x /p t, derived from known reactivities (log k) and ionization potential (fpot) of cyclohexane, cyclohexanone, 1,4-cyclohexadiene, cyclohexene, 1,4-dioxane, and piperidine, the ionization potential of 2,4,6-trimethyl-l,3,5-trioxane was calculated to be 8.95 eV <1987DOK1411>. 

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