Piperazine. 
Am.  Jour.  Pharm. 
April,  1893. 
lous  surfaces  were  more  or  less  covered  with  epidermis.  He  says 
also  that  it  is  of  use  in  gonorrhoea  of  women  with  ulcerations  in  the 
vagina  and  on  the  cervix  uteri. 
He  looks  upon  europhen,  then,  as  a  substitute  for  iodoform,  over 
which  it  has  the  advantage  of  causing  no  injurious  effects  after 
absorption,  and  having  no  unpleasant  smell. 
PIPERAZINE.1 
By  W.  Majert  and  A.  Schmidt. 
Erroneous  statements  have  appeared  in  several  modern  text- 
books regarding  the  physical  and  chemical  characters  of  piperazine, 
C4H10N2,  which  have  been  confused  with  those  ascribed  by  A.  W. 
von  Hofmann  and  by  Ladenburg  to  the  impure  substances  of  like 
composition  discovered  by  them,  and  termed  respectively  diethylene- 
diamine  and  ethyleneimine  or  diethylenediimine ;  our  attention  has 
been  directed  to  the  fact  that  this  misunderstanding  has  partly 
arisen  from  a  misconstruction  of  our  views  {Ber.,  1890,  3719)  as  to 
the  identity  of  these  substances  :  we,  therefore,  desire  to  correct  this 
impression. 
Piperazine,  which  was  not  known  in  its  pure  crystalline  condition 
until  prepared  by  us  in  August,  1 890,  by  treatment  of  dinitrosodi- 
phenylpiperazine  with  alkali,  is  a  crystalline  substance  melting  at 
104-1070  in  capillary  tubes,  although  when  the  melting  point  is 
determined  on  large  quantities  it  is  found  to  be  11 2°,  the  differences 
being  due  to  the  hygroscopic  nature  of  the  base;  it  boils  at  140— 
145 °.  It  is  very  readily  soluble  in  water  and  alcohol,  the  aqueous 
solution  having  a  distinctly  alkaline  action.  It  is  very  hygroscopic 
and  readily  absorbs  carbon  dioxide,  being  thereby  converted  into 
the  carbonate  melting  at  162-1650. 
Piperazine  is  especially  characterized  by  the  formation  of  an 
insoluble  pomegranate-red  double  salt  with  bismuth  iodide  and  by 
a  dibenzoyl  compound  melting  at  1.9 1 °. 
The  basic  substance  diethylenediamine  prepared  by  Hofmann  by 
the  interaction  of  ammonia  and  ethylene  bromide  consisted  of  a 
liquid  mixture  of  bases  boiling  approximately  at  1700.  That  this 
mixture  contained  a  small  quantity  of  a  base  identical  with  pipera- 
1Chem.  News,  March  3,  1893,  p.  108  ;  from  a  paper  read  before  the  Chemical 
Society. 
