psycosmo (Stranger)
08-03-01 11:42
No 200972
      Cyclization to phenethylamines  Bookmark   

I've been trying to find info on cyclizing substituted alkenes to their corresponding benzene compounds without much success. Is this possible? Could one say, cyclize a 1,2,3-trimethoxy 5-ethylamino hexene/hexane into mescaline, or a similar reaction for any other phenethylamine. I kmow its 2 EZ to be true but it seemed so potetially elegent I just had to post it....
 
 
 
 
    b159510
(Professional Student)
08-03-01 11:46
No 200974
      Re: Cyclization to phenethylamines  Bookmark   

Too easy? That would be a major pain.

Back to the Primitive
 
 
 
 
    Lilienthal
(Moderator)
08-03-01 19:05
No 201049
      Re: Cyclization to phenethylamines  Bookmark   

There is that nice cyclization / aromatization reaction to olivetol (analogs) starting from nonenone. I will post the ref later.
 
 
 
 
    Osmium
(Stoni's sexual toy)
08-03-01 20:14
No 201072
      Re: Cyclization to phenethylamines  Bookmark   

acetone + hexanal ---[aq. NaOH]---> 3-nonen-2-one 47% [1]

3-nonen-2-one + dimethylmalonate ---[NaOMe]---> complicated intermediate 70% [2]

complicated intermediate ---DMF, Br2, heat---> olivetol 85% [3]

[1] J. Gen. Chem. USSR 33, 134 (1963)
[2, 3] J. Org. Chem. 42, 3456 (1977)

best olivetol synth I know so far. Cheap, easy, yields ok. Starting with another aldehyde will yield olivetol analogs.