156 
Proceedings of Royal Society of Edinburgh. [sess. 
Preliminary Note on Dietthio and Diethylsulphone de- 
rivatives of Succinic Acid. By Professor Crum 
Brown and R. Fairbairn, B.Sc. 
(Read July 20, 1896.) 
I. Action of Sodium Mercaptide on Dibromosuccinic Ether. 
Sodium mercaptide and dibromosuccinic ether, in the proportion 
of two molecules of the former to one of the latter, were dissolved 
separately in absolute alcohol, and slowly mixed. A considerable 
evolution of heat took place, while sodium bromide separated out. 
The flask was then digested for some hours on the steam-bath. 
The alcohol was subsequently distilled off, and the residue, on 
cooling, was treated with water. An oil separated out. This 
oil was collected by means of a separating funnel, and the 
aqueous layer several times extracted with ether. The oil and 
the ethereal extracts were added together and dried over 
calcium chloride. Next morning the ether was distilled off at the 
ordinary pressure. The remainder was distilled in vacuo. Be- 
tween 50° and 60° a few drops came over, which proved to be 
ethyldisulphide. 
The remainder came over between 150° and 170°. 
This latter fraction was redistilled, and a portion of it used 
for analysis. The boiling point at 20 mm. pressure was 160°. 
Combustion of dietthiosuccinic ether. 
Weight of substance taken =’2477 gram. 
Weight of carbonic acid obtained = *4476 gram. 
Weight of water obtained = T702 gram. 
Calculated for C 12 H 22 S 2 0 4 . 
C = 49*0. 
H = 7*5. 
Found. 
C = 49*3. 
H = 7*6. 
