acid_egg (Hive Bee)
10-17-02 22:43
No 369670
      feasible new route to p2ps?  Bookmark   

I found this brief reference hinting at another route to p2ps.Could it also be useful for ring substituted p2ps too?Is it feasible or useful and if so can someone with access post it plz?

"...Tri-n-butyl tin methoxide reacts with isopropenyl acetate to give,in situ acetonyl tri-n-butyltin which undergoes a Pd catalysed coupling reaction with aryl bromides[bromobenzene] to give aryl acetones[phenyl-2-propanone]...."

                 n-Bu3SnOMe                          ArBr,PdCl2,P(o-tol)3
AcOCH(CH2)CH3   -------------->    n-Bu3SnCH2COCH3   -------------->   ArCH2COCH3

ref:Chem. Lett.,939 (1982)


Parts in red I have added.
 
 
 
 
    Rhodium
(Chief Bee)
10-23-02 00:14
No 371434
      Expensive Envirotoxin  Bookmark   

What's your price for the Bu3SnOMe? I see Acros carry it for $30/25g (with "Toxic" and "Envirotoxin" ratings), and considering that the molar weight is 321 g/mole, it is costly to employ it in stoichiometric amounts.

The Pd complex is just used as a catalyst.
 
 
 
 
    acid_egg
(Hive Bee)
10-23-02 23:16
No 371895
      ahhh...  Bookmark   


it is costly to employ it in stoichiometric amounts



Ah..of course..thats the kicker!

I think it was listed in mine at ~$75/100g.
That envirotoxin bit sounds about right as I believe its used as 'defoulant' for boats.(for barnacles and such I suppose.)

 
 
 
 
    josef_k
(Newbee)
11-07-02 06:05
No 377235
      You can also use isopropenyl acetate to make p2p .  Bookmark   

You can also use isopropenyl acetate to make p2p from an aniline via the diazotonium. I'm not so sure if it works without an electron withdrawing group on the ring though. The patent I saw it in made 3-trifluoromethyl-p2p. If anyone is interested it is Patent US5811586. Nevertheless it would be interesting to make the 4-tfm-amph.