548 



Dr. J. H. Gladstone and A. Tribe. [June 17, 



aluminium hydrate ; if aluminium be in excess, aluminic hydrate and 

 allylic iodide are the sole products. 



Aldehyde. — Hydrogen is not set free from this compound. 



The general result, then, of these observations is that the reagent 

 substitutes aluminium for the basic hydrogen of water, and of all the 

 alcohols hitherto tried, whether of the methyl, allyl, benzyl, or phenyl 

 series, with the remarkable exception of isopropyl alcohol. On the 

 other hand, it does not substitute aluminium for hydrogen in the 

 dihydric or trihydric alcohols, nor yet with aldehyde. The reaction 

 with the ethers and glycerine is of a different character, as, in addition 

 to an aluminium compound, the iodides of the positive radicals are 

 formed. 



General Properties of the Aluminium Alcohols. 



The aluminium alcohols are solid at the ordinary temperature, and 

 fuse generally into clear liquids. They possess, in a marked degree, 

 the property of remaining fluid far below their melting points. Those 

 of the methyl series distil unchanged at reduced pressures, affording 

 the first organic compounds which contain both oxygen and a metal 

 and are capable of distillation. They are soluble more or less in 

 ether, alcohol, and benzol, but are decomposed by water with the 

 formation of aluminium hydrate and the alcohols. 



They were found to have the following specific gravities at 4° 0. : — 



Ethylate 1-147 Phenylate ., . .. . . . 1*25 



Propylate 1-026 Cresylate 1-166 



Butylate 0*982 Thymolate...... 1*04 



Amylate 0'980 



Action of heat. — All these alcohols are decomposed at a temperature 

 somewhere about their boiling points, and it became an interesting 

 subject of inquiry whether they were resolved into alumina, and the 

 alcohol and its olefine, or into alumina and the ether. Both these 

 actions seem to take jilace. Thus aluminic ethylate appears to be 

 decomposed by heat in both ways, but mainly according to the following 

 scheme : — ■ 



(C 2 H 5 0) 6 A1 2 =A1 3 3 + 3C 2 H 4 + 3C 2 H 6 0. 



Aluminic phenylate on the other hand is capable of decomposition 

 mainly in the following way : — 



(C 6 H 5 0) 6 Al 3 =ALO + 3(C 6 H 5 ) 2 0. 



It must not however be supposed that these decompositions take 

 place without other reactions. Some of the bodies thus produced are 

 new ones, and we are at present engaged in their investigation. 



The most interesting decomposition is that of the thymolate. When 



