Decomposition carbonyl bromide chloride

This cyclization is a reaction developed by Mori, who carried out a series of investigations with tin reagent 33. Fluoride is a much more reactive anion for initiation than any of the other halides, although it often leads to decomposition of the starting materials. In the case of vinylic or aryl halogen compounds the iodides are easier to transform than the bromides, and chlorides are unrcactive. The carbonyl group can be derived from either an aldehyde or a ketone, and even esters are sufficiently electrophilic.22... 

The iron carbonyl halides are light-sensitive water converts them to the corresponding Fe (11) salt solutions (the chloride and bromide react instantaneously, the iodide only upon heating). The thermal decomposition of iron carbonyl halides is a convenient way to produce fine powders of anhydrous Fe(II) halides. 

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