154309-36-1Relevant academic research and scientific papers
Syntheses of (S)-fenfluramine from (R) or (S)-1-propan-2-ol
Goument, B.,Duhamel, L.,Mauge, R.
, p. 450 - 458 (2007/10/02)
(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
Epoxides, amino alcohols, and aziridines as key intermediates in the asymmetric synthesis of (S)-fenfluramine
Goument, B.,Duhamel, L.,Mauge, R.
, p. 459 - 466 (2007/10/02)
The epoxides 3E, 3Z and 8 were obtained from the isomeric alkenes 2E, 2Z and 7.The epoxides were ring-opened by ethylamine in ethanol yielding mixtures of the amino alcohols 4E and 11E, 4T and 11T, and 9, respectively, which were transformed into the aziridines 5trans, 5cis and 12.The regiospecific Pd/C-catalyzed reduction of these aziridines gave fenfluramine 1.The three epoxides 3trans, 3cis and 8 were reduced regiospecifically into 1-propan-2-ol 6, a potent precursor to fenfluramine 1.The validity of our method for asymmettric synthesis has been demonstrated by a synthesis of (S)-fenfluramine 1 starting from the amino alcohol (S)-9.Keyword - fenfluramine / asymmetric synthesis / epoxide / amino alcohol / aziridine / regiospecific catalytic hydrogenation / 1-propan-2-ols
