9734. s-Trioxane

Properties

Stable, cyclic trimer of formaldehyde possessing characteristic chloroform-like odor. Crystalline solid, mp 64°, bp₇₅₉ 114.5° without dec. Sublimes readily. Easily sol in water (17.2 g/100 ml at 18°, 21.1 g/100 ml at 25°), alcohols, ketones, ether, acetone, chlorinated and aromatic hydrocarbons, and other organic solvents. Only slightly sol in pentane, petroleum ether, and lower paraffins. d⁶⁵ 1.17. Flash pt 45°C. On distillation with water, forms an azeotrope boiling at 91.4° containing approx 70% trioxane by wt. Slowly depolymerized by strong acids in aq soln, but inert to alkalies. In non-aqueous systems, readily converted to monomeric formaldehyde by small concentrations of strong acids at a rate determined by the acid concentration.