Greene] ^O [ 0ct ]7j 



tomic chloride present, the organic radicle entering the benzol nucleus, and 

 aluminium chloride being reformed. 



C 6 II">. AV-'Cl 5 + CIFCl = 6 II 5 . GIF -f- A1 2 C1 8 



A small quantity of aluminium chloride serves for the preparation of an 

 indefinite quantity of the new hydrocarbon. 



By the action of aluminium chloride on the monatomic chlorides alone, 

 hydrochloric acid is also eliminated, and the radicle is condensed. Hence, 

 the reaction which would take place between benzol and a polyatomic 

 chloride under the same circumstances cannot be entirely foreseen. It 

 seems possible that in the case of ethylene chloride, for example, both 

 atoms of chlorine might be replaced by phenyl groups, but it would seem 

 more probable that, after the first substitution, one molecule of hydrochlo- 

 ric acid would be removed from the ethylene chloride, and that a more 

 condensed hydrocarbon, styrol, would be formed. However, the first re- 

 action is that which actually occurs. 



When aluminium chloride is introduced into a mixture of benzol and 

 ethylene chloride, the reaction begins iu the cold, and becomes energetic 

 on the application of heat. Hydrochloric acid is disengaged abundantly ; 

 when the reaction has ceased, the mixture is thrown into water to separate 

 the aluminium chloride, and the oil)' liquor which separates is heated with 

 alcoholic potassium hydrate, in order to decompose any remaining ethylene 

 chloride. 



After washing and drying the product, it yields, on fractional distilla- 

 tion, very nearly the theoretical quantity of dibenzyl, after which a thick 

 oily mixture remains, which does not completely distill at 200° in a vacuum. 

 This mixture consists of condensation products, and yields no satisfactory 

 results, as it cannot well be fractionated, and does not solidify in a freezing 

 mixture. 



Pure dibenzyl melts at 52.5-53°, and boils at 279°, under a pressure of 

 767 millimetres, the thermometer being entirely immersed in the vapor. 

 This boiling point is lower than that given by Cannizarro and Rossi (284°), 

 and higher than that indicated by Fittig (272°). 



On Dioxy ethyl methylene, and the Preparation of Methylene chloride. By 

 Wm. H, Greene, M.D. 



{Read before the American Philosophical Society, November 21, 1879.) 



"With the exception of the diethyl ether of methylene glycol, all of the 

 oxyethyl substitution compounds of methane havo already been described. 

 Orthoformic ether, CH(OC 2 H 5 ) 3 , was studied by Kay and Williamson, and 

 is generally known as Kay's ether; orthocarbonic ether, C(OC 2 H 3 )*, was 

 discovered and described by H. Bassett : methyl-ethyl oxide has long been 

 known. 



By a reaction similar to that by which these ethers are formed, I have 



