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T A H I. E I. 



süinc (louhl aliout this. In difluse davliiflit oifJto- and parahvomo- 

 toluene are also t'ormed acrordinu- to liini ; Erdm.vnx, on the otliei' 

 hand, stated that lienzylbroinide is the sole prodnet. The observations 

 of Dr. V.\N DV.K L.\AN confirm tliose of Erdm.vnn. In diffuse davlight 

 the broniination proceeds very rapiiliy at 25° : in aliout 10 minutes 

 all the bromine has disappeared. The analysis of the product gave 

 99"'„ of benzylbromide. From this it follows that pure benzylbromide 

 can be readily jireparcd in this manner. Bkii-stkin, who attempted 

 this previously, arrived at the opposite result. This, however, was 

 caused by the fact liiat lie exposed to the light a mixture of bromine 

 and toluene in equivalent proportions at the temperature of boiling 

 toluene. Operating in this manner we obtain indeed a product with- 

 out a constant boiling point wliicii on fractionation appears to con- 

 Iain products boiling at higiier tempei'atures. If, however, working 

 in the iigiit and al IdO", only one niol. of bromine is used for 'JO 

 niois. of toluene, the formation of these higher boiling substances is 

 [U'exenled. 'ihe excess of lobuMic is rea<lily remo\ed liy distillation. 

 After a distillation in \acuo l)r. Van df.u Law obtained a product 

 .solidifying at -- 4^3 of a sp. gr. I .;5.s,s7 at tin .5 whilst these con- 

 stanls. accordinu to his observations, ai-e — 3'. 9 and 1.3(S.5<S at ()5\5 

 for piiiv benzylbromide from benzylalcohol. The benzylbromide thus 

 jin'parcd contains, therefore, less than 0.5" „ of impurities. 



3. /ii/hifiirc (if (_'iitii/;/:t'rs. As the intluence of light is, as we 

 ha\'e seen. \ery great, all the (wperiments with catalyzers were made 

 in complete darkness. Of the>e were tested : antimony tribromide, 

 aluniiniumbromide, ferricbromide and phosphornstribromide. Of the 

 first three it is stated that they favoui- the broniination in the core, 

 of the latter that it accelerates the formatitm of benzylbromide. The 

 observations of Dr, Van der Laan are in harmony with this. The 



