Halous acids, HOXO, and halites

Chlorous acid is the least stable of the oxoacids of chlorine it cannot be isolated but is known in dilute aqueous solution. HOBrO and HOIO are even less stable, and, if they exist at all, have only a fleeting presence in aqueous solutions. Several chlorites have been isolated and NaC102 is sufficiently stable to be manufactured as an article of commerce on the kilotonne pa scale. Little reliable information is available on bromites and still less is established for iodites which are essentially non-existent. 

HCIO2 is formed (together with HCIO3) during the decomposition of aqueous solutions of CIO2 (p. 847) but the best laboratory preparation is to treat an aqueous suspension of Ba(C102)2 with 

SOLYMOSI, Structure and Stability of Salts of the Halogen Oxyacids in the Solid Phase, Wiley, UK, 1978, 468 pp. 

The Halogens Fluorine, Chlorine, Bromine, Iodine and Astatine 

In addition to the applications indicated on p. 858. hypohalous acids are useful halogenating agents for Ixjth aromatic and aliphatic compounds. HOBr and HOI are usually generated in silii. The ease of aromatic halogenation increa.ses in the sequence OCl OBr Ol and is facilitated by salts of Pb or Ag. Another well-known reaction of hypohalites is their cleavage of methyl ketones to form carboxylates and haloform  

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