Protium (Stranger)
09-04-01 19:22
No 210050
       Tri-alkyl silane / TFA reduction of aryl ketone  Bookmark   

Well, this is my first post - and I'm here to ask if anyone has attempted the direct reduction of the benzyl -OH of pseudoephedrine to afford methamphetamine using Et3SiH / TFA ?

It's a rxn used to reduce aryl carbonyl groups back to the methylene, however, as it goes through the alcohol intermediate, you'd think this would work?  If no one writes back I'll try it out and post my write up.  Should go 99% or so according to the paper.  Not so bad, using 2.2 equiv. Et3SiH + 10-15 equiv TFA - stir.. rxn over in 15 mins..

off to the pharmacy..cool 		 
 
 
 
    Rhodium
(Chief Bee)
09-04-01 19:42
No 210055
       Re: Tri-alkyl silane / TFA reduction of aryl ketone  Bookmark   

I believe Dave Nichols used that method to reduce a cathinone to an amphetamine in the synthesis of the compound mentioned in the thread "New amphetamine more potent than LSD" in this forum... 		 
 
 
 
    Lilienthal
(Moderator)
09-05-01 00:25
No 210143
       Re: Tri-alkyl silane / TFA reduction of aryl keton  Bookmark   

NaBH4 / TFA should work also. 		 
 
 
 
    jim
(Hive Bee)
09-05-01 03:24
No 210173
       Re: Tri-alkyl silane / TFA reduction of aryl keton  Bookmark   

LiAlH4/ AlCl3 in ether works to reduce benzyl alcohols. REFERENCE:"The Journal of Organic Chemistry", Vol 29, yr 1964, page 110-115 		 
 
 
 
    akata
(Hive Bee)
09-05-01 15:02
No 210343
       Re: Tri-alkyl silane / TFA reduction of aryl ketone  Bookmark   

Post 183270 (The_Animal: "Triethylsilane", Stimulants) might be useful
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