Am.  Jour.  Pharrn.  \ 
December,  1907.  J 
Synthetic  Camphor, 
551 
The  solution  should  be  allowed  to  stand  an  hour,  at  least,  with 
moderately  weak  solutions. 
Oil  of  cinnamon  is  a  frequent  condiment  in  food  products,  and 
the  above  shows  clearly  that  when  these  are  examined  for  benzoic 
acid,  the  cinnamon  is  likely  to  mislead.  If  a  crystalline  body  is 
obtained  in  the  process  of  separating,  the  usual  tests  cannot  be 
relied  upon  to  distinguish  between  the  two  acids.  It  is  difficult  to 
get  the  acid  in  a  pure  enough  condition  to  identify  it  by  the  melting- 
point,  and  the  sublimation  test  is  also  unreliable. 
If  a  precipitate  is  obtained  with  ferric  chloride  in  neutral  solution, 
the  liquid  should  also  be  tested  with  solutions  of  manganous  sulphate 
(or  chloride).  A  precipitate  with  this,  after  an  hour's  standing, 
shows  cinnamic  acid.  If  no  precipitate  occurs  benzoic  acid  is 
indicated. 
SYNTHETIC  CAMPHOR. 
By  Frank  Tutin. 
In  the  August  number  of  this  Journal,  pp.  349-356,  there 
appeared  a  contribution  from  Mr.  L.  F.  Kebler  (Chief  of  the  Drug 
Laboratory,  Washington,  D.  C),  entitled  "Synthetic  Camphor," 
which  was  intended  by  the  author  to  be  a  response  to  the  requests 
received  by  the  Bureau  of  Chemistry  for  information  on  this  subject. 
In  the  above-mentioned  communication  an  account  was  given  of 
the  various  processes  which  have  been  devised  for  the  synthetic 
production  of  camphor,  and  the  chemical  changes  involved  therein 
were  illustrated  by  means  ot  structural  formulae.  In  view  of  the 
purpose  which  the  paper  was  intended  to  serve,  it  appears  somewhat 
unfortunate  that  it  should  contain  a  number  of  inaccuracies,  and  as 
these  are  so  fundamental  in  their  nature,  it  would  seem  desirable 
that  attention  should  be  drawn  to  them. 
The  author,  for  example,  has  represented  the  changes  involved  in 
the  conversion  of  pinene  into  camphor  by  means  of  the  following 
formulae : 
CH2— 
CH,— 
CH3 
I 
-C — 
I 
■C — CH, 
CH2- 
CH3 
-C  — 
CHC1 
HC1 
CH 
CH,— C— CH, 
 > 
—  HC1 
CH, 
CH, 
CH, 
•c— 
I 
-CH 
-CH 
Pinene. 
CH2  CH 
Bornyl  chloride. 
CH, 
C 
I 
CH2  CH  
Camphene, 
CH 
