Anhydrous Zirconium Bromide

Zirconium bromide, anhydrous, 1 49 Zirconium complex compounds, nonelectrolytes, with acetylacetone, ZrCCsHjOili-lOHaO, 2 121 Zirconium oxybromide, formation of, from zirconium bromide, 1 51... 

Air- and moisture-sensitive complex cyanides of composition M5Zr(CN)5 (M = K or Rb) have been prepared by reaction at -50 °C in anhydrous ammonia of zirconium(III) bromide with an excess of either KCN or RbCN. In the case of the reaction involving KCN, the 1 3 distribution of zirconium between the gray, ammonia-insoluble K5Zr(CN)5 and the soluble zirconium(IV) products is in accord with the disproportionation shown in equation (1). The... 

Direct reaction of zirconium and hafnium tetrahalides and bromides with excess DMSO under strictly anhydrous conditions yielded products of composition Zr(Hf)Cl4 9DMSO and Zr(Hf)Br4 lODMSO (482). Attempts to recover the tetrahalides by heating only resulted in the production of tarry residues. The S-O-stretching frequency in these compounds was found to be 960 cm" for the nine-solvate and 920 cm for the 10-solvate, which indicates that the DMSO molecules are oxygen bound. 

The alkylation of paraSins with olefins to yield higher molecular weight branched-chain paraffins may be carried out thermally or catalyt-ically. The catalysts for the reaction fall into two principal classes, both of which may be referred to as acid-acting catalysts (1) anhydrous halides of the Friedel-Crafts type and (2) acids. Representatives of the first type are aluminum chloride, aluminum bromide, zirconium chloride, and boron fluoride gaseous hydrogen halides serve as promoters for these catalysts. The chief acid catalysts are concentrated sulfuric acid and liquid hydrogen fluoride. Catalytic alkylations are carried out under sufficient pressure to keep at least part of the reactants in the liquid phase. 

---