- 18 - 
was designed to determine both rotenone and deguelin, it will "be discussed 
only briefly here and described in more detail in the section on Depruelin 
and fiotenone Plus Deguelin. The root sample was extracted with ether and 
after crystallization of a first crop of rotenone from the extract the 
evaporated mother liquor was oxidized so that there were formed dea;-dTo- 
rotenone, from the remaining rotenone, and dehydrorieCTielin. The mixture 
of insoluble dehydro compounds was separated and weighed. It was then 
subjected to catalytic hydrogenation under suitable conditions, when the 
dehydrorotenone was converted to the alkali-soluble isodihydxoder^dro- 
rotenone while the dehydroc'e^Tuelin remained -unchanged, thus in effect 
giving separate values for rotenone and deguelin. Some (?erris-root 
samples gave s-urprisingly large amounts of additional rotenone by this 
method. In one extreme case only 0.56 percent of lotenone was obtained 
by crystallization, while an additional 4.74 percent was obtained by the 
chemical treatment of the n^other liquor. On the other hand, in a sample 
giving 6.38 percent of rotenone b-" crystalli-^ation only 0.52 percent of 
additional rotenone was obtained. Values or. some other sajnples ranged 
between theee extremes. One sample giving no rotenone by ether crystalliz- 
ation gave 0.97 percent by the chemical metnod. Later work by Tatters- 
field and ilartin (120) , however, has shown that the ether crystallization 
used by Takei and coworkers was inco^iplete. 
In the same year Danckwortt and Budde (24), in an investigation 
of methods for the evaluation of derris root, proposed the separation of 
rotenone by extraction with chloroform followed by crystallization from 
ether. The powdered root was covered with 10 times its weight of chloro- 
form, and the mixture allowed to stand for 24 hovrs with frequent agitation, 
An aliquot of the ciloroform extract equivalent to six-tenths of the 
original sample was filtered, the chloroform removed, and the residue 
crystallized from ether. 
In 1934 DancKwortt, Budde, and Baum^rarten (25) reviewed various 
crystallization method's for the determination of rotenone in derris and 
described other means of evaluation. The ether-extraction method of 
Koolhaas (78) was said to be too long. They considered the Jones (62) 
carbon tetrachlorir^e method to be good only for rotenone contents above 
4 percent. The method of Takei, Miyajima, and Cno ( 118 ) was said to be 
unobjectionable theoretically but ver^- troublesome and time-consuming. 
The method of Danckwortt and Budde (24) was also mentioned. 
G-stirner (51) in 1934 compared results by the polarimetric method 
with those by the ether-extraction and crystallization method. The much 
lower results by the latter method were explained as largely due to part 
of the rotenone remaining; in t'^.e mother liquor. 
Cahn and Boara (13) in 1935 made an extensive study of the deter^-nina- 
tion of rotenone in 'Ferris root and resin, nvhen derris resins were dis- 
solved in carbon tetrachloride to peoarate tne crystalline solvate, the 
eolubilitv was said to be increased to an unusual extent by the presence 
of the resin. 'A maximum :"ield of rotenone was obtained when 2 cc. of 
carbon tetrachloride (saturated v/ith rotenone) was used to dissolve each 
gram of resin. Room temperature was adopted for cr^'-stallization and fil- 
tration, as little difference was found between results obtained at 0^ and 
