Am.  Jour.  Pharm. 
Sept.,  1893. 
Oil  of  Erigeron  Canadense. 
425 
The  limonene  «-nitroso  chloride  was  converted  into  a  benzyl- 
amine  base,  which  when  dried  melts  from  92-930  C.  (Melting 
point  for  limonene  a-nitrolamine  as  observed  by  Wallach1  is  the 
same,  i.e.,  92-93 0  C.) 
Fraction  II  (170-172°). — Of  this  fraction  a  nitroso  chloride  was 
also  prepared  and  purified  as  described  above.  The  melting  point 
of  the  tabular  crystals,  from  the  ethereal  solution,  when  dried,  was 
from  99-1020  C.  A  benzylamine  base  was  made  of  the  limonene 
nitroso  chloride,  which  when  dried,  melted  from  91-92-5°  C. 
Fraction  III  (172-174.°). — The  limonene  «-nitroso  chloride  pre- 
pared from  this,  when  purified  and  dried,  melted  at  from  99-103°  C. 
The  benzylamine  base  of  this  when  dried,  melted  at  from  91-92-5°  C. 
Fraction  IV  (17  4-175°). — Although  there  can  be  but  little  doubt  as 
to  the  largest  per  cent,  of  this  fraction  being  limonene,  traces  of 
foreign  bodies  have  covered  the  odor  of  this  hydrocarbon.  In  order 
to  bring  out  the  limonene  odor,  these  foreign  bodies  were  removed 
by  treating  a  portion  of  the  fraction  with  permanganate  of  potash 
solution.  To  200  cc.  of  a  half  per  cent,  of  permanganate  of 
potash  solution,  10  cc.  of  oil  were  added.  This  after  standing  for 
twelve  hours  discolored  the  solution.  The  oil  was  separated  and 
added  to  fresh  solution  of  permanganate  of  potash.  This,  upon 
standing  in  the  cold  for  twenty-four  hours,  did  not  change  color. 
The  original  odor,  however,  of  the  oil  had  been  changed  to  that 
of  pure  limonene. 
Fraction  V  (175-176°). — Of  this  fraction  a  nitroso  chloride  was 
also  prepared,  which  when  pure  melted  from  99-103°  C.  The 
benzylamine  base,  into  which  the  limonene  nitroso  chloride  con- 
verted, when  dried,  melted  at  90-92°  C. 
These  results  verify  the  statement  that  Erigeron  oil  consists  chiefly 
of  dextrogyrated  limonene.  Even  these  fractions,  which  possessed 
a  somewhat  higher  or  lower  boiling  point — evidently  consist  almost 
entirely  of  this  hydrocarbon,  the  boiling  point  of  which  is  slightly 
depressed  or  raised  by  other  substances.  The  thought  that  pinene 
possibly  occurred  together  with  limonene  in  the  oil  evidently  must 
be  dismissed.  The  principal  constituent  of  the  oil  besides  limonene 
appears  to  be  a  high  boiling  substance,  probably  aldehyde-like  in 
Annalen,  p.  136. 
