Am.  Jour.  Pharm. ) 
Feb.,  1882.  j 
Chemical  Notes. 
71 
to  menthone  in  a  similar  relation  to  that  which  borneol  stands  to  cam- 
phor. The  menthol  thus  prepared  from  menthone  melts  at  42'2°C.j, 
but  has  a  rotatory  power  of  — 39.  The  authors  then  prepared  men- 
thene,  CioH^g?  t>y  heating  menthol  with  zinc  chloride;  the  crude  pro- 
duct was  purified  by  careful  fractionation  and  long  digestion  with 
sodium.  The  pure  product  distilled  over  constantly  at  167*4°C. 
Menthene  is  a  colorless  liquid,  moderately  soluble  in  ether  and  alcohol, 
more  soluble  in  benzene,  turpentine  and  petroleum.  By  treating  men- 
thol with  hydriodic  acid,  distillation,  treatment  with  caustic  soda, 
sodium,  etc.,  a  colorless  hydrocarbon  was  obtained,  which  consisted 
chiefly  of  CjoH^g,  with  a  small  quantity  of  C^oH^g  or  Q^^^^, — Chem. 
News,  Dec.  9,  1881,  p.  283. 
On  the  Transfoi^mation  of  Morphine  into  Codeines  and  Homologous 
Bases. — The  formula  of  morphine,  Cj^H^gNOs,  and  that  of  codeine, 
CigH2iN03,  show  that  these  two  bases  differ  from  each  other  by  CHg, 
and  that  codeine  may  be  considered  as  derived  from  morphine  by  the 
substitution  of  a  CHg  group  for  one  atom  of  hydrogen.  How  tried, 
in  1853,  the  action  of  methyl  iodide  upon  morphine;  but  he  obtained 
an  isomer  of  the  hydriodate  of  codeine,  presenting  none  of  the  char- 
acteristics of  an  alkaloid  salt.  More  recently,  Matthiessen  and 
Wright  have  determined  something  of  the  relation  of  morphine  to 
codeine.  By  heating  morphine  with  hydrochloric  acid,  they  extracted 
the  elements  of  water,  and  obtained  as  a  result  apomorphine.  Codeine,, 
submitted  to  the  same  treatment,  likewise  yielded  apomorphine  and 
also  methyl  chloride.  There  is,  therefore,  present  in  morphine  an 
alcoholic  OH  group,*"and  in  codeine  a  group  OCH3.  E.  Grimaux,  in 
considering  these  reactions,  observed  that  morphine  resembled  the 
phenols  in  its  characteristics,  and  it  occurred  to  him  that  codeine 
might  be  the  methyl  ether  of  morphine,  considered  as  a  phenol.  It 
then  only  remained  to  try  this  transformation  by  the  usual  means, 
viz. :  heating  with  alcoholic  potash  or  soda.  Morphine  was  dissolved 
in  alcoholic  soda  solution,  the  proportions  being  one  molecule  of  mor- 
phine to  one  molecule  of  soda,  and  a  quantity  of  methyl  iodide,  cor- 
responding to  two  molecules,  added.  On  gently  heating  the  mixture,, 
brisk  action  took  place,  which  ceased  after  a  few  minutes.  The  reac- 
tion took  place  in  the  manner  expected ;  but  was  complicated  by  a 
secondary  reaction,  and  in  the  place  of  free  codeine  there  was  obtained 
the  iodomethylate  of  codeine,  CH3l,Ci7HjgN03(OCH3).     The  com- 
