136816-63-2

Upstream product

• 135561-76-1 Toluene-4-sulfonic acid (S)-1-methyl-2-(3-trifluoromethyl-phenyl)-ethyl ester 
• 135561-75-0 (S)-1-[(3′-trifluoromethyl)phenyl]-2-propanol 
• 21906-39-8 3-(trifluoromethyl)phenylacetone 
• 135561-78-3 (R)-1-(3’-trifluoromethylphenyl)-2-propanol 
• 401-78-5 3-bromo-1-trifluoromethylbenzene 
• 154140-19-9 2-(methylsulfonyloxy)-1-<3-(trifluoromethyl)phenyl>propane 
• 136816-62-1 Toluene-4-sulfonic acid (R)-1-methyl-2-(3-trifluoromethyl-phenyl)-ethyl ester 

Downstream Products

• 3239-44-9 dexfenfluramine 

Relevant academic research and scientific papers

Syntheses of (S)-fenfluramine from (R) or (S)-1-propan-2-ol

(R) and (S)-1-propan-2-ol 3 are useful intermediates in the synthesis of fenfluramine (S)-1.They can be obtained from optically active propylene oxide (R) or (S)-7.The alcohol (R)-3 was transformed in two steps into (S)-fenfluramine using the action of ethylamine on a sulfonate (R)-4.We describe a new one-pot synthesis for (S)-fenfluramine from the azide (S)-5, which was obtained from the alcohol (R)-3 in two steps.We also propose an original and rapid procedure to transform the alcohol (S)-3 into (S)-fenfluramine via the chloride (R)-14 and the azide (S)-5, without preliminary inversion of the alcohol.All of these reactions have been achieved without any loss of chirality.Keywords - 1-propan-2-ol / fenfluramine / asymmetric synthesis / chiral methyloxirane / nucleophilic substitution