622 
Sesquiterpenes. 
f  A.ni.  Jour  Pharuu 
I        Dec.,  1892. 
soluble  in  ether,  alcohol,  and  most  other  solvents.  In  the  solid 
state  it  is  almost  without  smell,  but  the  vapor  has  the  odor  of  pine 
needles.  The  chemical  characters  of  this  substance  prove  it  to  be 
an  alcohol.  The  chloride,  bromide,  iodide  and  nitrite  were  prepared  ; 
they  are  crystallizable  substances,  optically  inactive  and  very  stable. 
The  iodide  subjected  to  the  action  of  sodium  yielded  a  crystallizable 
hydrocarbon,  melting  at  1 35 °  C,  which  gave,  on  analysis,  results 
pointing  to  the  formula  C30H50,  and  at  least  showing  that  the  treat- 
ment had  given  rise  to  the  production  of  a  hydrocarbon  of  high 
molecular  weight,  closely  related  to  the  terpene  group. 
Dehydrating  agents  convert  the  alcohol  into  a  liquid  hydrocarbon, 
clovene,  boiling  between  261 0  and  2630  ;  its  specific  gravity  was 
0930  at  1 8°  C.  Its  composition  is  represented  by  the  formula 
C15H24,  but  as  it  could  not  be  reconverted  into  the  alcohol  it  was 
evidently  distinct  from  caryophyllene. 
Out  of  a  large  number  of  oils  containing  sesquiterpenes  only  one 
was  found  to  yield  material  from  which  the  above  described  alcohol 
could  be  obtained  in  the  same  manner.  The  fraction  of  copaiba  oil, 
distilling  between  2500  and  2700,  gave  the  desired  result,  and  the 
crystalline  alcohol  prepared  from  it  proved  to  be  identical  with  that 
from  clove  oil.  The  identity  of  this  hydrocarbon  with  that  in  clove 
oil  was  also  proved  by  the  production  of  -a  nitroso  chloride 
C15H24N0C1,  a  white  sparingly  soluble  powder  that  blackened  and 
decomposed  at  161-1630,  and  was  readily  converted  by  reaction 
with  piperidine  into  a  nitrolamine. 
The  terpenes,  C10H16,  are  known  to  be  susceptible  of  reduction  to 
hydrocarbons  of  the  formula  C^H^,1  and  by  operating  upon  the 
dihydrochloride,  C15H242HC1,  with  hydriodic  acid,  a  hydrocarbon  of 
the  composition  C15H2S  was  obtained,  the  characters  of  which,  as 
compared  with  those  of  the  original  sesquiterpene,  are  as  follows : 
The  sesquiterpenes  may  be  classed  in  two  groups,  those  with  one 
ethylene  bond  and  those  with  two.  The  best  known  representative 
of  the  latter  is  the  frequently  occurring  laevorotatory  sesquiterpene, 
which  forms  with  two  molecules  of  hydrochloric  acid  a  well-defined 
•918 
274-2750 
Specific  gravity, 
Boiling  point,  . 
•872 
257-2600 
1  Berthelot,  Jahresb.,  1S69,  333. 
