Tetrabutylammonium Dibromobromate I

The checkers prefer to remove remaining bromine by a vacuum operation. 

References cited are the same as those listed for synthesis 46 (p. 175). 

See also Preparation of metal derivatives of 1,3-diketones, synthesis 29 Anhydrous metal chlorides, synthesis 43 

Submitted by Karl H. Gayer and Leo Woontner Checked by Russell S. DragoJ and Thomas Shepherd J 

Hydrated iron(II) chlorides are usually prepared by dissolving pure iron in hydrochloric acid solution and crystallizing.1,2 The hydrate formed depends upon the temperature of crystallization,1,2 the 6-hydrate forming below 12.3°, the 4-hydrate above 12.3°, and the 2-hydrate above 72.6°. Contamination by iron(III) is difficult to avoid in the majority of these procedures. Samples of the 2-hydrate free from iron(III) can be obtained conveniently from the commercially available 4-hydrate by recrystallization in the presence of pure iron in an inert atmosphere. 

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