Sulfur Trioxide-1,4-Dioxane

(x unspecified) [54287-50-2] C4H8O5S (MW 168.19) (x = 1) [20769-58-8; 35346-47-5] C4H8O8S2 (MW 248.26) InChI = 1S/C4H8O2.O3S/c1-2-6-4-3-5-1;1-4(2)3/h1-4H2; InChIKey = HGBGABMSTHQFNJ-UHFFFAOYSA-N (x = 2) [52922-31-3] C4H8O11S3 (MW 328.33) InChI = 1S/C4H8O2.2O3S/c1-2-6-4-3-5-1;2*1-4(2)3/h1-4H2;; InChIKey = NTHGLQVCZIRQNS-UHFFFAOYSA-N (x = 3) [52922-32-4] InChI = 1S/C4H8O2.3O3S/c1-2-6-4-3-5-1;3*1-4(2)3/h1-4H2;;; InChIKey = VZBNWRDNLDRWOZ-UHFFFAOYSA-N (useful for effecting Beckmann rearrangements;8 sulfonation of alkenes11 and arenes16) Physical Data: mp 75 °C,2 but almost never isolated. Solubility: generated as a solution in dioxane, with or without other solvents. Preparative Methods: the Organic Synthesis procedure2 involves reaction of Sulfur Trioxide (as Sulfan B) with dioxane in 1,2-dichloroethane. The complex precipitates and is used immediately. An alternate procedure involves treatment of dioxane with ClSO3TMS,3 itself prepared by reaction of Chlorotrimethylsilane and Chlorosulfonic Acid.4 Handling, Storage, and Precautions: reacts vigorously with water, alcohols, etc. It has been reported to decompose violently upon standing at rt2 or upon heating to 75 °C.5 The chemistry is essentially that of SO3 with some attenuation in reactivity. Safety precautions in the handling of SO3, which can be an unexpectedly strong oxidant, should be followed.1c