Am  jour.  riKu-m.  /    JJrethanes  of  Thymol  and  CarvacroL  123 
Februarv,  1921.     )  ■>  ° 
l 
An  hydroxyl  group  is  present  because  it  dissolves  in  5  per  cent, 
sodium  hydroxide  with  a  slight  color,  and  this  deepens  on  standing 
or  boiling.  When  carefully  neutralized  with  hydrochloric  acid  it  is 
precipitated  out  again. 
The  residue  which  melted  at  266-270°  was  small  in  quantity 
and  was  known  to  be  mixed  with  the  urea  derivative ;  so  it  is  not 
known  whether  the  diurethane  forms  under  these  conditions,  or  in 
what  proportion  it  may  be  present. 
Application  to  Hydrothymoqitinone  Dimethyl  Ether. — The  ether 
(  2.0  g.  )  and  phenyl  isocyanate  (2.4  g. )  were  boiled  with  20  cc.  of 
petroleum  under  a  reflux  for  an  hour.    On  cooling  a  few  crystals 
appeared  which  were  probably  diphenyl  urea.    It  was  boiled  another, 
hour  and  nothing  came  out. 
Leuckart1Ta  discovered  that  thymol  methyl  ether  reacts  with 
17:1  Leuckart,  J.  pr.  Chemie.  II.  p.  320. 
phenyl  isocyanate  in  the  presence  of  aluminum  chloride.    The  re- 
sulting product  is  methylisopropyl  methoxyl  benzanilide. 
Accordingly  this  reagent  was  added  to  the  reaction  mix 
ture.  W  arming  to  boiling  initiates  a  spontaneous  reaction,  which 
keeps  the  mixture  in  gentle  ebullition  for  a  few  minutes.  The  color 
did  not  change,  but  on  heating  crystals  began  to  appear  and  a  liquid 
distilled  into  the  condenser  which  returned  to  the  flask  in  drops, 
causing  sputtering. 
The  product  was  filtered  from  the  petroleum,  decomposed  with 
cold  dilute  hydrochloric  acid  and  taken  up  in  alcohol,  in  which  it  is 
as  readily  soluble  and  as  easily  recovered  as  the  monourethanes. 
The  color  was  discharged  by  boiling  with  bone  black.  After 
crystallization  once  from  alcohol  1.5  g.  were  recovered.  It  melted 
at  240-241  °.  Re-crystallized,  it  melted  at  240-241  °,  and  treated  with 
boneblack  at  240°  exactly.  The  crystals  are  white,  appear  as  radiat- 
ing clusters  of  needles  and  resemble,  in  solubility  also,  the  mono- 
urethanes of  thymol  and  carvacrol. 
Upon  digestion  in  sulphuric  acid,  it  gave  an  oil  which  steam 
distilled  at  first  but  dissolved  and  cleared  up  completely  in  one  and 
one-half  hours. 
I.i  0.2984  g.  required  29.11  cc  N/10  HC1. 
II.  o.'3io8g.  required  30.20  cc  N/10  HC1. 
Found 
Nitrogen  4-    i3-'6/ p.  c. 
IJ.    13.65  p.  c. 
Ua  Leuckart.  J.  pr.  Chemie,  II.  p.  320. 
