432 
Benzylidine  Dipiperidine. 
Am.  Jour.  Pharm. 
Sept.,  1893. 
Crystalline  Sulphur  Compound. — After  removal  of  the  amorphous 
sulphur  compound  from  the  alcoholic  solution  of  benzylidine  dipiperi- 
dine the  mother  liquor  was  set  aside  in  a  cool  place. 
After  standing  for  several  weeks  crystals  began  to  form,  at  first  very 
slowly,  but  later  on  quite  rapidly,  continuing  until  the  entire  liquid 
had  evaporated.  This  would  seem  to  indicate  that  by  the  action  of 
hydrogen  sulphide  on  benzylidine  dipiperidine,  in  alcoholic  solution, 
two  compounds  at  least  are  formed. 
The  sulphur  in  this  crystalline  compound  estimated  as  barium 
sulphate  gave  the  following  results : 
I.  0*1556  grams  yielded  0*3144   grams  BaS04  =  0*0431  S 
11.0-1948       "        "      0-40894      "     BaS04  =  0-05616  S 
Found. 
Calculated  for  t  '  s 
CnH3oN2S3  I.  II. 
26-81  p.  c.  27-12  28-02 
The  result  of  this  sulphur  estimation  agrees  fairly  well  with  the 
results  obtained  by  Mr.  Tompkins. 
This  compound,  when  thoroughly  purified  by  recrystallization, 
yields  crystals  of  a  grayish  white  color  having  a  melting  point  of 
75-76°  C.  They  are  soluble  in  alcohol,  from  which  they  recrystal- 
lize  readily.  This  compound  is  permanent  in  the  air  and  when 
boiled  with  water  separates  oily  drops  which  float.  It  fuses  at  a 
gentle  heat  and  upon  cooling  crystallizes  without  apparent  change. 
Benzylidine  Aniline. — Since,  by  the  action  of  hydrogen  sulphide 
on  benzylidine  dipiperidine,  two  very  interesting  compounds  were 
obtained,  it  was  thought  well  to  ascertain  if  similar  results  could  be 
obtained  with  other  condensation  products  of  benzaldehyde.  To  this 
end  benzylidine  aniline  was  prepared  in  the  following  manner  :  4-3 
grams  of  aniline  was  added  to  a  solution  of  5  grams  of  benzaldehyde 
in  10  grams  of  petroleum-ether.  The  mixture  is  heated  on  a  water- 
bath  in  a  flask  connected  with  an  inverted  condenser  for  fifteen  min- 
utes. The  solution  is  then  filtered  and  set  aside  to  crystallize.  It  crys- 
tallizes very  readily,  a  large  yield  being  obtained.  From  fifteen  grams 
of  benzaldehyde  10-34  grams  of  benzylidine  aniline  were  obtained 
or  68*92  per  cent.  This  was  dissolved  in  alcohol  and  a  current  of 
hydrogen  sulphide  led  into  the  solution  when  a  grayish  amorphous 
compound  separated  out  similar  to  that  obtained  from  benzylidine 
dipiperidine.  From  10  34  grams  of  benzylidine  aniline,  7-08  grams 
of  the  amorphous  compound  were  obtained  or  68-4  per  cent.  This 
