Results of Experiments. 
259 
WITH ISOPROPYL ALCOHOL. 
So far, experiments with isopropyl alcohol have been, no more 
successful than those with methyl alcohol. An evolution of hy¬ 
drogen takes place on the addition of the stannic chloride and 
continues, if the temperature is kept at that of the water bath, 
until a solid mass is formed; but no distillate can be obtained 
on heating under diminished pressure. Here, again, indications 
are that the isopropylate is formed but decomposes on heating. 
WITH AMYL ALCOHOL. 
With this alcohol it has been found that the amylate can 
readily be obtained. It is of a dark yellow color and boils at 
291° C., under a pressure of 12 mm. No analysis has as yet 
been made of it. 
The reaction involved in the formation of these alcoholates 
would seem at first thought to be very simple, since the product 
is a compound in which the aluminium has replaced, in each 
molecule of alcohol, one atom of hydrogen. This change in 
composition could be expressed, with common alcohol, by the 
equation 
3 C 2 H 5 O H + A1 = (C 2 H 5 0) 3 A1 + 3 H. 
But this does not explain why it is necessary, for the prog¬ 
ress of the reaction, to have present other things besides alco¬ 
hol and metallic aluminium. By the initial reaction, when the 
stannic chloride is added, metallic tin is precipitated on the 
aluminium, and aluminium chloride is formed thus: 
2 A1 + Sn Cl 4 == Sn A1 + A1 Cl 3 + Cl. 
Both of these products seem to have an influence, as it is found 
that aluminium will not dissolve in alcohol in presence of tin 
alone and but slowly when aluminium chloride is present with¬ 
out the tin. The reaction is probably due to the action of the 
aluminium, or some compound of aluminium chloride with the 
alcohol, under the strain of the electric couple of which the tin 
and the aluminium are the negative and positive metals. The 
alcoholates so formed are themselves of considerable interest be¬ 
cause they are one of a very small class of organo-metallic bodies 
containing oxygen which can be distilled, and because they 
