208  Urethanes  of  Thymol  and  Carvacrol.    -j  AlM^h '  f92irm' 
further.    The  derivatives  of  the  heavy  metals  formed  amorphous 
precipitates : 
Pb  —  yellow 
Ca  =  yellowish-red 
Cu  =  bright  green 
Zn  =  yellowish-white 
Cd  =  reddish-yellow 
Ag  =  deep  red 
Goldschmidt  and  Schmid  20  obtained  the  silved  salt  as  a  brown 
precipitate  by  adding  silver  nitrate  to  a  solution  of  nitrosothymol  in 
ammonia,  and  obtained,  on  analysis,  37.53  per  cent,  silver,  compared 
with  a  theoretical  content  of  37.72. 
For  the  preparation  of  alkali  derivatives  the  corresponding 
nitrosophenol  was  dissolved  in  the  theoretical  quantity  of  2N  alkali, 
made  up  free  from  carbonate,  and  allowed  to  evaporate  to  dryness 
in  a  vacuum  desiccator.  v 
Sodium  Nitrosocarvacrol.  —  Nitrosocarvacrol  dissolves  very 
readily  in  sodium  hydroxide,  giving  a  clear,  reddish-brown  solu- 
tion, and  evaporates,  leaving  a  reddish-brown  crystalline  mass,  with 
some  bright  green  masses  forming  long  thin  crystals  radiating  in 
clusters.  The  crystals  are  ruby  red  by  transmitted  light,  of  rectan- 
gular shape,  and  pulverize  to  a  maroon  powder.  This  substance  was 
stable  at  ioo°.  It  decomposes  suddenly  and  intumesces  slightly  on 
heating  to  a  high  temperature  with  evolution  of  reddish  vapors  and 
leaves  a  brown  oily  sublimate.  It  was  dissolved  in  about  six  times 
its  weights  of  absolute  alcohol,  filtered  and  precipitated  by  adding 
it  to  a  large  excess  of  ether.  Reddish  crystals  appeared  at  once,  and 
it  was  obtained  as  a  bright  maroon)  crystalline  powder.  Sodium 
was  determined  by  conversion  into  the  sulphate  and  calculated  to  the 
basis  of  the  substance  dried  at  ioo°. 
0.3712  g.  lost   0.0416  g.  at  ioo° 
I.  0.2007  g.  gave  0.0635  g.  Na2S04 
II.  0.2012  g.  gave  0.0636  g.  Na2S04 
Found         Calc.  for  C10H12NO2Na 
Loss  at  ioo°  1 1. 21  p.  c.         iH20  =   8.23  p.c. 
2H20  =  15.20  " 
Sodium  on  dried  basis  Ij  11.30 p.c.  H-44  " 
II.  11.30  " 
The  yield  of  sodium  derivative  recovered  in  this  manner  was 
90.3  per  cent,  by  weight. 
20  Goldschmidt  and  Sc'.imid,  Ber.,  17  (1884),  p.  2062. 
