A^^uar^yPl902^m•}    Coal  Tar  Derivatives  and  Morphine.  35 
COLOR  REACTIONS  OF  CERTAIN  COAL-TAR  DERIVA- 
TIVES AND  MORPHINE  WITH  FORMALDEHYDE 
AND  SULPHURIC  ACID. 
By  Robert  A.  Hatcher,  M.D. 
A  description  given  in  a  recent  journal  of  the  reaction  occurring 
between  formaldehyde-sulphuric  acid  and  several  coal-tar  derivatives, 
salicylic  acid  and  its  compounds,  resorcin,  creasote  and  carbolic 
acid,  resulting  in  a  purple  color,  so  closely  agrees  with  that  of  the 
color  produced  by  the  reaction  between  this  reagent  and  morphine 
(Kobert)  as  to  cause  possible  confusion.  If  the  reactions  were  so 
similar,  as  would  seem  from  the  description,  this  test  would  have  but 
a  limited  value  in  the  case  of  morphine. 
A  reaction  similar  to  that  mentioned  in  the  case  of  coal-tar  deriv- 
atives is  given  by  the  formaldehyde-sulphuric  acid  and  aspirin 
(acetyl-salicylic  acid),  and  is  ascribed  by  Thorns  (Pharm.  Ztg.y  XLVI, 
p.  5  53)  to  the  phenol  residue  of  salicylic  acid. 
In  order  to  decide  whether  the  reaction  with  morphine  is  distin- 
guishable from  those  afforded  by  the  substances  mentioned,  a  number 
of  comparative  experiments  were  made.  An  alkaline  solution  of 
carbolic  acid  (I)  was  taken,  and  for  the  sake  of  more  accurate 
comparison  the  same  amounts  of  sodium  hydrate  and  sulphuric  acid 
were  used  in  the  morphine  solution  (II)  and  in  that  of  carbolic 
acid  and  morphine  (HI). 
The  reagent  is  made,  according  to  Kobert,  by  mixing  5  c.c.  of 
formaldehyde  (40  per  cent  )  with  100  c.c.  of  sulphuric  acid.  The 
colors  were  compared  with  a  sample-card  of  the  Diamond  Dye 
Company. 
The  following  six  substances  were  used,  the  results  being  found 
in  the  table  below : 
N  N 
I.  -i   gm.  Carb.  acid  4-  5  c.c.  —  NaOH  warmed  and  10  c.c.  — 
&  1  J        10  10 
H2S04  added. 
N  N 
II.  -oi  gm.  Morphine  sulphate  -f  5  c.c.  —  NaOH  -f  10  c.c.  — 
H2S04. 
III.  -I  gm.  Carb.  acid  +  -oi   gm.  morphine  sulphate  -f  5  c.c. 
N  N 
—  NaOH  warmed,  and  10  c.c.  —  H2S04  added. 
N 
IV.  -i  gm.  Sodium  salicylate  (com'l)  -f-  50  cc.  —  H2S04. 
