36 
Chlor  acetones. 
Am.  Jour.  Pharm. 
Jan.,  1888. 
has  no  fixed  boiling  point,  and  is  not  attacked  by  ammonia  at  the 
ordinary  temperature.    It  is  not  a  tetrachloracetone. 
When  the  product  of  the  oxidation  of  dichlorhydrin  is  treated  with 
bromine,  it  yields  an  isomeride  of  dichlorodibromacetone,  which,  ac- 
cording to  Markownikoff,  has  the  constitution  CHClBr'CO'CHClBr. 
Wiien  this  compound  is  treated  with  mercuric  chloride,  however,  it 
yields  a  liquid  which  fumes  in  the  air,  boils  at  about  180°,  has  a  dis- 
agreeable odor,  and  does  not  combine  with  alkaline  hydrogen  sul- 
phites. With  ammonia  or  aniline,  it  yields  neither  chloroform  nor 
phenylcarbylamine,  but  dichloracetamide  and  dicliloracetanilide  re- 
spectively. It  folloAvs  that  either  there  are  two  isomeric  symmetrical 
tetrachloracetones,  or  that  the  product  of  the  oxidation  of  dichlor- 
hydrin is  not  an  acetone  derivative,  as  already  indicated. 
When  symmetrical  iodacetone  is  treated  with  silver  chloride,  and 
the  product  is  treated  with  bromine  and  afterwards  with  mercuric 
chloride,  a  liquid  is  obtained  which  boils  at  180°,  and  is  identical 
Avith  symmetrical  tetrachloracetone.  The  dichloracetooe  from  iodace- 
tone has  always  been  regarded  as  identical  with  MarkownikofF's 
products,  but  these  results  show  that  they  are  very  different,  and  the 
latter  is  most  probably  a  derivative  of  epichlorhydrin — 
CH2C1*CH<  Q^QJ>- 
Pentachloraaetone  was  obtained  by  Staedeler  by  adding  hydrochloric 
acid  to  a  boiling  solution  of  quinic  acid  and  potassium  chlorate.  The 
yield  is  very  small,  and  great  care  is  required  to  avoid  explosions. 
Much  better  results  are  obtained  by  the  following  method.  A  solution 
of  citric  acid  in  1*5  parts  of  water  is  allowed  to  fall  drop  by  drop 
down  a  tube  packed  with  pumice,  up  which  passes  a  current  of  dry 
chlorine,  the  tube  being  heated  at  100°  by  means  of  a  water-jacket. 
The  product  is  purified  by  washing  and  redistillation.  If  the  water 
used  for  washing  is  evaporated  at  a  low  temperature,  it  deposits 
crystals  of  citric  acid  which  contain  2  mols.  II2O,  and  are  quite  dif- 
ferent in  appearance  from  the  ordinary  crystals.  They  form  flattened 
prisms  with  four  of  the  faces  abnormally  developed.  The  cleavage 
planes  and  the  angles  at  the  edges  are,  however,  identical  with  those 
of  the  ordinary  crystals. 
The  pentachloracetone  obtained  is  identical  with  that  prepared  by 
Staedeler  and  by  Cloez,  sen.,  by  the  action  of  chlorine  on  alkaline 
citrates.    With  ammonia,  it  yields  chloroform  and  dichloracetamide,. 
