ON TMe STUUV Oi-' liVDiiO^AROiViAl'lC SUBSTANCEfci. 



223 



riie folluwing is a tabulated comparison of the properties of tliis 

 hydrocarbon with those of the dimethyldihydrobenzene prepared by 

 Crossley and Le Sueur : — 



B.p 



Sp. gr. at 15°/15° . 

 Index of refraction . 

 Molecular refraction 

 Magnetic rotaiion . 

 Colour with H^SO^ . 



Fuminff HBr . 



Bromine . . . . 



NOCl . . . . 



Nitrating mixture . 



Oxidation products , 



Oxidation products of 

 monohydrobroujide 



DimethyldiliydrobeuEeues 



(C and S) 



to 



111° 



0-8153 

 1-4518 

 00-217 

 11024 

 Blood-red turning 



violet -purple 

 Monohydrobromide, b. p 

 yO-o°/3G mm. 



Dibromide, unstable 

 liquid 



Nitrosochloride, m. p. 



121° 

 No definite product 



as-dimethylsuccinic acid 



ftx-diiDethylsuccinic acid, 



/8y8-dimethylglutaric acid, 



lactone of o-bydruxy-^yS- 



dimethylglutaric acid 



(C and Rj 



to 



P- 



111-2° 

 U-8147 

 1-4535 

 CO-251 

 10-450 

 Blood-red turning 



vioiet-puiple 

 Monohydrobromide, b 



83°/20 mm. 

 Dihj drobromide, b. 



137°/25 mm. 

 Dibromide, unstable 



liquid 

 Tetrabromide, m. p. 102° 

 Nitrosochloride, m. p. 



121° 

 Trinitro-«-sylenes, m. p. 



71° and 115° 

 a«-dimethylsuccinic acid, 

 dimethylmalonic acid 

 ««-dimetbylsuccinic acid, 

 /3;8-dimetby]glutaric acid, 

 lactone of c;.-hydroxy-/3/3- 



dimetbylglutaric acid 



From the above table the most important chemical properties of 

 dimethyl-A-=^ dihydrobeuzene and dimethyl- A'-^-'-dihydrobenzene would 

 appear to be : — 



The criticisms of Harries and Antoni {loc. cit.) may then be replied to 

 as follows. 



In the first place, these authors consider that the analyses given by 

 Crossley and Le iSueur (ibid.) are midway betweeu those for a dimethyl- 

 dihydro- and a dimethyitetrahydro-benzene. The mean of the two analy- 

 ses quoted gave C=S8-30 and H=;ir27, and it is obvious from the 



annexed comparison that the numbers do not lie midway between tho 



