100 G. M. BENNKTT AND E. E. TURNER. 



NOTE ON ORGANO-METALLIO DERIVATIVES OF 

 CHROMIUM, TUNGSTEN AND IRON. 



By George Macdonald Bennett, m.a., m.sc, and 

 Eustace Ebenezer Turner, b.a., m.sc 



(Communicated by Prof. J. Read). 



[Read before the Royal Society of N.S. Wales, August 6, 1919-2 



It has been shown 1 that anhydrous chromic chloride reacts 

 with aryl-magnesium halides to give compounds which, on 

 decomposing with mineral acids, are quantitatively con- 

 verted into the respective di-aryl hydrocarbons. The 

 nature of the intermediate compounds, usually (as in the 

 case of the product from phenyl magnesium bromide) orange- 

 red in colour, has not yet been determined, owing to the 

 difficulty of isolating pure substances from the reaction- 

 mixtures, but in view of some experiments (carried out in 

 1914) on the interaction of phenyl magnesium bromide and 

 anhydrous ferric chloride, the view is now expressed that 

 in the case, both of chromic and ferric chlorides, organo- 

 metallic derivatives are formed, these being decomposed 

 in presence of mineral acid, so that in the preliminary 

 experiments their formation escaped observation. 



Of the two series of organo-metallic compounds, the iron 

 compounds are apparently the more stable. The chromium 

 intermediate compound (phenyl) on treatment with mineral 

 acid, is at once converted into diphenyl, whereas the iron 

 compound is partly so decomposed, the major portion 

 remaining in the ethereal solution. Thus in one experiment,, 

 a Grignard reagent prepared from 37*5 grams of bromo- 

 benzene, 4*6 grams of magnesium and 50 ccs. of ether was 



1 Trans. Chem. Soc, 1914, 105, 1057. 



