1918-19.] 
Researches in Optical Activity. 
31 
Ethyl d-Tartrate in Ethylene Bromide. 
p = 9-840. 
Densities : — 
t . . . .16°* 17*75° 39*7° 43° * 60° * 79'5°* 100°* 
d 2-0158 2-0160 1-9745 1-9691 1-9365 1*9006 L’8574 
* Experimental. 
Length, of tube used, 50 mm. 
t. 
a (100 mm.). 
[4 
[M], 
Q 
Q 
Q 
Q 
r l ■ 
17-7 
39-7 
-1-580 
0-850 
-7-96 
4-37 
-16-41 
9-01 
r 2 . . 
17-7 
39-7 
- 2-006 
1-112 
-10-11 
5-72 
- 20-83 
11-79 
y 
17-7 
39-7 
-2-544 
1-530 
-12-82 
7-88 
-26-42 
16-22 
9 
17-7 
39-7 
-3-164 
1-936 
-15-95 
9 96 
-32-86 
20-53 
b 
17-7 
39-7 
-4-728 
3-156 
-23-83 
16-24 
- 49-09 
33-46 
V 
17-7 
39-7 
-7'914 
5-476 
-3990 
28-19 
-82-18 
58-06 
Isobutyl Dibenzoyl-d-tartrate. 
Forty-six grams of 'isobutyl tartrate and 100 grams of benzoyl chloride 
were heated together, under a reflux condenser, in an oil-bath at 140°-150° 
for about two hours, the heating then being continued at 185° until no 
further reaction appeared to take place. The excess of benzoyl chloride 
was removed under reduced pressure, and the residue fractionally distilled. 
The portion boiling between 200°-280° at 10-mm. pressure was dissolved in 
benzene and the liquid shaken with sodium carbonate solution, separated, 
and heated on the water-bath with animal charcoal for about six hours. 
After drying with fused calcium chloride, the benzene was removed and 
the ester fractionally distilled. It boiled in the neighbourhood of 240* 
under 3-mm. pressure. 
