Am.  Jour.  Pharm. 
Jan.,  1888. 
Chlor  acetones. 
39 
product  dissolved  in  water,  a  tetrahydrate  is  formed  which  can  be 
recrjstallized.  It  is  decomposed  by  hydrochloric  acid,  and  when  the 
liquid  thus  obtained  is  dried,  it  boils  at  130°  under  a  pressure  of 
25  mm.,  and  at  215°  under  normal  pressure  ;  sp.  gr.=:2*270.  It  has 
a  pungent,  irritatiag  odor.  The  hydrate  is  only  slightly  soluble  in 
water,  but  dissolves  more  readily  in  alcohol  of  80°,  from  which  it 
crystallizes  in  large,  hexagonal  tables  containing  1  mol.  HoO ;  this  is 
readily  given  off  even  on  exposure  to  the  air.  With  aqueous  ammonia 
at  a  low  temperature,  chlorotribromacetone  yields  bromoform  and 
chloracetamide,  and  therefore  has  the  constitution  CBrg-CO'CHoCl. 
So-called  dichlorodibromacetone,  obtained  by  the  action  of  bromine  on 
pseudodichloracetone,  is  a  liquid  which  solidifies  at — 14°,  melts  at 
— 8°,  and  boils  at  135°  under  a  pressure  of  40  mm.  It  does  not 
combine  with  alkaline  hydrogen  sulphites.  It  forms  a  tetrahydrate, 
which  crystallizes  in  long  prisms  melting  at  53 — 54°  with,  partial  de- 
composition. The  action  of  ammonia  shows  that  this  compound  con- 
tains neither  CClsBr  nor.CBroCl,  and  hence  its  constitution  must  be 
CHBrCl-CH<^'^>. 
The  action  of  bromine  on  dichlorhydrin  yields  a  compound  which 
boils  at  140 — 141°  under  a  pressure  of  20  mm.  It  forms  a  crystal- 
line tetrahydrate  which  melts  at  55 — 56°,  and  boils  with  partial  de- 
composition at  140 — 150°  under  a  pressure  of  20  mm.  It  is  not 
identical  with  the  preceding  compound,  and  may  have  the  constitution 
CBr2Cl-CH<™^^>. 
The  action  of  bromine  on  ordinary  dichloracetone  yields  a  liquid 
which  boils  at  . 120°  under  a  pressure  of  25  mm.,  and  does  not  solidify 
at  a  low  temperature.  It  forms  a  tetrahydrate  which  crystallizes  in 
hexagonal  tables  with  a  very  disagreeable  odor;  these  readily  lose 
their  water.  Barbaglia's  dichloracetone  boiling  at  170°  yields  the 
same  derivative  with  bromine,  and  is  therefore  a  polymeride  of  ordi- 
nary dichloracetone.  Dibromodichloracetone  reacts  energetically  with 
ammonia,  but  no  chlorobromoform  is  produced,  and  hence  the  com- 
pound must  have  the  constitution  CHCl2'CO-CHBr2.  With  mer- 
curic chloride,  it  yields  a  tetrachloracetamide  which  does  not  contain 
the  group  CCI3. 
When  trichloracetone  is  treated  with  bromine  at  100°,  it  yields  a 
trichlorobromacetone,  which  boils  at  107°  under  a  pressure  of  25  mm., 
