41 8  Pennyroyal  Oil.  {^i^lXm™' 
American  oil  contains  pulegone  or  not,  the  following  study  was 
undertaken. 
PULEGONEOXIME. 
The  difficulties  in  preparing  the  oxime,  from  the  American  oil, 
were  overcome  by  proceeding  in  the  following  manner :  To  20 
parts  of  the  oil,  12  parts  of  hydroxylamine  hydrochlorate,  with  14 
parts  of  sodium  bicarbonate,  and  a  mixture  of  30  parts  of  ether 
and  10  parts  of  alcohol  are  added.  The  mixture  was  allowed  to 
stand  overnight,  and  then  heated  for  two  hours  on  a  water-bath, 
and  filtered  while  hot.  Almost  immediately  crystals  of  the  oxime 
appeared. 
A  number  of  modifications  of  this  process  had  previously  been 
tried,  only  one  of  which  was  successful,  besides  the  above  men- 
tioned. The  modification  in  this  case  consisted  in  heating  the  mix- 
ture for  one  hour,  before  allowing  it  to  stand  overnight.  The 
crystals  of  oxime  obtained  melted  at  137-1380  C.  The  melting 
point  was  raised  to  1470  C.  by  recrystallization,  from  a  mixture  of 
three  parts  of  ether  and  one  part  of  alcohol. 
Dried  over  calcium  chloride  this  oxime,  corresponding  in  appear- 
ance to  pulegoneoxime  of  Beckmann  and  Pleissner,1  yielded  upon 
analysis  the  following  results : 
(I)  0-2946  grams  of  the  substance  yielded,  0-6980, C02  =  0-1903  C 
and  o-2856,H20  =  0-0317  H 
(II)  0*2184  grams  of  the  substance  yielded,  0-5196,003  —  0-1417  C 
and  o'2044,H20  =  0-0227  H 
(III)  0-1878  grams  of  the  substance  yielded,  0-4438, C02  =  0-1210  C 
and  o-i8i8,H20  =  0-0202  H 
(IV)  0*1382  grams  of  the  substance  yielded  io'2  cc.  of  nitrogen  under  a 
barom.  pressure  of  728  mm.,  and  at  a  temperature  of  210  C.  ==  o'oin  grams 
nitrogen. 
(V)  0-1964  grams  of  the  substance  yielded  15  cc.  of  nitrogen  under  a 
barom.  pressure  of  743  mm.,  and  at  a  temperature  of  190  C.  =  0-0168  grams 
nitrogen. 
Calculated  for 
Obtained. 
Ci0H16NOH,H2O.  I.  II.  III.  IV.  V. 
C,   64-86  64-59  64'88  64-43  —  — 
H,   10*27  10-76  10*39  1075  —  — 
N,   7'57                —             —  —  8-03  8-57 
O,   1730               —            —  —  —  — 
From  the  above  results,  it  will  be  seen,  that  no  doubt  can  exist, 
1  Ann.  d.  Chem.,  Bd.  262,  p.  6. 
