Chlorosulfiiric acid

This method is also used with alcohols of the structure Q(CH2)kOH (114). Halo alkyl chlorosulfates are likewise obtained from the reaction of halogenated alkanes with sulfur trioxide or from the chlorination of cyclic sulfites (115,116). Chlorosilanes form chlorosulfate esters when treated with sulfur trioxide or chlorosulfiiric acid (117). Another approach to halosulfates is based on the addition of chlorosulfuric or fluorosulfuric acid to alkenes in nonpolar solvents (118). 

The [SeCl3]+ ion is also formed in chlorosulfiiric acid containing 802012 or selenium and chlorine. ... 

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