154 
Constituents  of  Amyl  Nitrite. 
/  Am.  Jour.  Pharm. 
\      March,  1889. 
Two  specimens  of  the  official  "  amyl  nitrite  "  have  been  examined  ; 
both  of  them  were  obtained  of  well-known  manufacturers.  In  order 
to  separate  a  sufficient  quantity  of  the  constituent  nitrites  for  identifi- 
cation, recourse  was  had  to  several  series  of  fractional  distilla- 
tions. 
The  first  specimen  examined  had  been  obtained  from  a  maker  of 
great  repute.  Half  a  litre  was  distilled  from  a  flask  fitted  with  a  long 
tube  carrying  a  T-piece,  the  thermometric  column  being  entirely  im- 
mersed in  the  vapor. 
The  liquid  commenced  to  distil  at  77°  C,  and  the  following  nine 
fractions  were  collected.  A  dark-colored  residue  containing  amyl  al- 
cohol and  other  substances  remained  in  the  flask. 
I.     77°-  82°   =    30  cc. 
II.     82°-  88°   =    23  cc. 
III.  88°-  93°   =  140  cc. 
IV.  93°-100°   =  138  cc 
V.    100°-105°   =    52  cc. 
VI.    105°-110°   ,         =    24  cc. 
VII.    110°-120°   =    17  cc. 
VIII.   120°-125°   =    12  cc. 
IX.    125°-132°   =    20  cc. 
This  process  of  fractional  distillation  was  repeated  five  times  with 
each  of  these  nine  portions.  A  considerable  quantity  of  liquid  was 
thus  obtained  between  67°-69°,  and  again  between  94°-98°.  These 
liquids  were  again  distilled  and  the  fractions  collected  at  67°,  and  96° 
respectively.  The  specific  gravity  of  the  liquid  boiling  at  67°  was  as- 
certained to  be  0*8755  at  15°  (water  at  15°— 1).  The  nitrite  was  es- 
timated in  the  compound,  and  it  was  found  to  correspond  almost  ex- 
actly with  that  contained  in  iso-butyl  nitrite  (0.1756  gram,  of  liquid 
yielded  an  amount  of  nitric  oxide  corresponding  to  '1746  gram. 
C4H9N02).  The  physical  and  chemical  properties  of  the  liquid  were 
thus  shown  to  be  identical  with  those  of  pure  iso-butyl  nitrite.  This 
compound  constituted  about  10  per  cent,  of  the  original  "  amyl  ni- 
trite." The  liquid  which  boiled  nearly  constantly  at  96°  was  next 
examined.  Its  specific  gravity  was  0*878  at  15°  (water  at  15°=1)» 
The  amount  of  nitrite  contained  in  it  was  almost  the  same  as  that  con- 
tained in  amyl  nitrite  (0  211  gram  yielded  an  amount  of  nitric  oxide 
corresponding  to  0*2099  gram  of  C5HnN02).  This  liquid  was  evi- 
dently a  mixture  of  a-amyl  nitrite  (b.  p.  97°)  and  ,3-amyl  nitrite  (b.  p. 
94°  circa).    The  presence  of  the  /9-amyl  nitrite  was  proved  by  the 
