OP ARTS AND SCIENCES. 



211 



TABLE V. 



The product of the last experiment was washed, boiled with alcoholic 

 sodic acetate, and then heated in a scaled tube with aqueous ammonia, 

 when crystals of the paraehlorbenzylalcohol were obtained, showing 

 that even in presence of 1 per cent of iodine a portion of the bromine 

 enters the side-chain. This result was confirmed by some experiments 

 on toluol, in one of which toluol was mixed with 10 pe? cent of iodine 

 and treated with chlorine at 120°; on fractioning the product, about 

 one half passed over from 164°— 222° (chlortoluol boils from 156°- 

 160°), attacked the nose violently, and gave an amine when heated in 

 a sealed tube with alcoholic ammonia; it must, therefore, have con- 

 tained benzylchloride, boiling-point 176°, and probably chlorbenzyl- 

 chloride, boiling-point 213°. In another experiment it seemed that 

 even 40 per cent of iodine was not enough to completely prevent the 

 formation of benzylbromide at 111°; but the determination of the ben- 

 zylbromide by the amine process was interfered with by the presence 

 of iodine substitution products to such an extent that we can place but 

 little reliance on this result. 



Summary. 



I. The portion of Beilstein's Law which states that benzyl-com- 

 pounds are formed at high, and substituted toluols at low temperatures, 

 is confirmed by our experiments. 



II. The benzyl-compound begins to be the principal product near 

 the boiling-point of toluol (111 ); in other words, no connection can 

 be traced between the boiling-point of a substituted toluol and the 

 temperature at which the bromine begins to enter its side-chain in 

 quantity. Above 111 there is a gradual increase in the amount 

 formed as the temperature is raised; but the total increase from 111° 

 to the boiling-point of the substance is usually smaller than the increase 

 from 100° to 111°. 



III. The rate at which the bromine is taken up becomes more rapid 

 as the temperature is raised. 



IV. Toluol takes up bromine more rapidly than its substitution pro- 



