304 PROFESSOR A. CRUM BROWN AND DR JAMES WALKER ON THE 



The less soluble acid fused, when rapidly heated, with decomposition, at 192°. 

 Zelinsky and Bitschichin * give 191° as the fusing-point of " fumaroid " diethylsuccmic, 

 acid, Bischoff and Hjelt 189°-190° for that of para-s-diethylsuccinic acid. 



Combustion gave the following results : — 



0-1252 gramme gave 0'2530 gramme C0 2 aad 00915 H 2 0. 



Calculated for C 8 H 14 4 . Found. 



C 5517 5511 



H . 8-05 812 



The acid had thus the expected composition. The basicity was determined by titration 

 with baryta water. 0*0846 gramme acid required for neutralisation 9*10 cc. of 1/9*45 

 normal baryta water. 



Calculated for C 6 H 12 (COOH) 2 . Found. 



Carboxyl-hydrogen . 1-150 1138 



The dissociation constant was determined with the following result : — 



Para-s-diethylsuccinic acid prepared by electrolytic synthesis. 



COOH-CH(C 2 H 5 )CH(C 2 H 5 )-COOH. 



Moo =351 . 



V 



fj- 







100m 



K 



65-85 



412 







11-74 



00237 



1317 



566 







1612 



0-0235 



2634 



77-2 







2200 



00235 



527 



1035 







29-5 



00234 



054 



136-6 



K = 



= 0-0235. 



38-9 



00235 



Bischoff and WALDENt found the value K = 0-0245. 



The more soluble acid, after repeated recrystallisation from water and from benzene, 

 fused at 130°. Bischoff and Hjelt give 129° as the fusing-point of anti-s-diethyl succinic 

 acid. Zelinsky and Bitschichin J give 126°-127° as that of " malenoid " diethylsuccmic 

 acid. 



The following results of analysis agree with the formula C 6 H 12 (COOH) 2 : — 



0-1224 gramme gave 0"2465 gramme C0 2 and - 0894 gramme H 2 0. 

 Calculated for C 8 H 14 4 . Found. 



C . . . . 5517 5493 



H . . . . 805 812 



0'0822 gramme required for neutralisation 8 - 90 cc. l/9'45 normal baryta water. 

 Calculated for C 6 H 12 (COOH) 2 . Found. 



Carboxyl-hydrogen, 1'150 1146 



* Berichte der deutschen chemischen Gesellscliaft 21, 3399. 

 + Ibid., 22, 1821. % Ibid,, 21, 3399. 



