CHLORAL. 
455 
CHLORAL. 
By  C.  a.  Martius  and  P.  Mendelsohn-Bartholdy. 
In  the  course  of  our  experiments  on  the  preparation  of  hy 
drate  of  chloral,  it  fell  in  our  way  to  examine  different  prepara- 
tions found  in  commerce,  the  purity  of  which  was  guaranteed  by 
crystallization  from  sulphuret  of  carbon  and  ether,  and  subse- 
quent pressing  out.  Our  attention  w^as  also  directed  to  the 
varying  statements  respecting  the  points  of  fusion  and  ebullition 
of  hydrate  of  chloral,  and  to  the  possibility  of  admixture  of 
foreign  substances,  even  after  the  renewal  of  free  chlorine  and 
hydrochloric  acid,  and  notwithstanding  its  solubility  and  appa- 
rent homogeneity  ;  and  that  to  these  foreign  substances  might 
be  due  the  discrepancies  relative  to  physical  properties,  and  pos- 
sibly also  the  physiological  discrepancies  found  by  different  ob- 
servers. We  were  especially  struck  by  the  differences  in  boiling- 
point  in  different  preparations,  and  led  to  the  preparation  of  a 
series  of  compounds  which  threw  light  upon  these  discrepancies, 
and  which  are,  moreover,  of  some  scientific  interest. 
It  had  been  observed  by  J.  Personne*  that  chloral  enters  into 
combination  with  alcohol  just  as  it  does  with  water.  According 
to  our  observations,  the  other  alcohols  of  the  fatty  series  behave 
similarly  to  ethylic  alcohol.  When  one  equivalent  of  chloral  is 
mixed  with  one  equivalent  of  anhydrous  ethylic  alcohol,  there 
is  union  accompanied  with  development  of  heat,  and,  on  cooling, 
the  resulting  compound  solidifies  into  a  crystalline  mass.  The 
same  takes  place  when  methylic,  butylic,  or  amylic  alcohol,  or 
mercaptan,  is  substituted  for  ethylic  alcohol. 
We  may  regard  .these  compounds  as  intermediate  trichlor- 
acetals. 
Acetal. 
Trichloracetal. 
Chloral-hydrate. 
Chloral  alcoholate 
Chloral  amylate, 
Chloral  rnercaptide. 
*  "  Comptes  Rendus,"  vol.  Ixix,  p.  1363. 
