3i8 
Reactions  of  Cocaine. 
Am,  Jour.  Pharrn. 
June,  1892. 
and  potassium  bichromate,  and  ferric  chloride,  the  alkaloid  or  its 
salts  give  no  characteristic  reaction.  It  has  been  stated  that  with 
the  sulphuric  acid  and  bichromate  test  cocaine  gives  a  dirty  pink, 
but  with  this  I  have  not  been  able  to  obtain  any  distinct  coloration. 
The  following  are  some  of  the  characteristic  reactions  of  which 
notices  have  been  published  from  time  to  time  as  being  useful  for 
the  identification  of  the  alkaloid.  ■ 
Cocaine  treated  with  an  alcoholic  solution  of  potassium  hydrate 
yields  ethyl  benzoate  with  characteristic  odor. 
Professor  Fluckiger,  in  a  paper  published  in  the  Pharmaceutical 
Journal  of  March  20,  1886,  draws  attention  to  the  fact  that  if 
cocaine  or  its  salts  be  heated  with  sulphuric  acid  sp.  gr.  1-84,  white 
acrid  vapors  are  given  off  which  on  cooling  deposit  crystals  of 
benzoic  acid.  This  reaction,  he  states,  may  be  performed  with 
minute  quantities  of  the  alkaloid. 
Schell  remarks  that  a  mixture  of  cocaine  hydrochloride  and  a 
small  quantity  of  mercurous  chloride  moistened  or  simply  breathed 
upon  blackens.  Atropine  gives  the  same  result,  but  only  on 
heating.  The  alkaloid  cocaine  does  not  answer  to  this  test,  but 
only  its  hydrochloride. 
Vitali  proposes  a  test  which  consists  in  dissolving  the  alkaloid 
in  y2-\  cc.  of  sulphuric  acid  in  a  porcelain  capsule  and  adding 
potassium  or  sodium  iodate  or  iodic  acid,  in  the  proportion  equal 
to  three  times  the  weight  of  the  cocaine,  when  on  slightly  heating 
on  a  water-bath  light  green  streaks  appear,  then  a  grass  green 
coloration,  and  last  a  dark  blue. 
There  is  a  test  proposed  by  de  Silva,  which  was  commented 
upon  by  Mr.  Stark  at  a  meeting  of  this  Association  last  session. 
It  consists  in  evaporating  to  dryness  on  a  water-bath  a  solution 
of  a  minute  portion  of  cocaine  or  one  of  its  salts  in  nitric  acid 
sp.  gr.  i«4,  and  then  treating  the  residue  with  an  alcoholic  solution 
of  potash,  when  an  odor  similar  to  that  of  peppermint  is  developed. 
Mr.  Stark,  in  his  note,  mentioned  that  he  had  tried  this  test  with 
atropine,  sabadilline,  pilocarpine,  cinchonine,  eserine,  veratrine, 
brucine,  codeine,  delphinine,  narcotine,  qumine,  strychnine,  and 
quinidine,  none  of  which  yielded  a  result  similar  to  that  of  cocaine, 
though  he  thought  the  odor  of  the  product  from  the  latter 
suggested  citronella  rather  than  peppermint,  and  was  not  distinctive 
enough  to  render  the  test  reliable.    The  odor  that  I  have  obtained 
