41958-65-0Relevant academic research and scientific papers
Chiral Lewis base promoted trichlorosilane reduction of ketimines. An enantioselective organocatalytic synthesis of chiral amines
Guizzetti, Stefania,Benaglia, Maurizio,Cozzi, Franco,Annunziata, Rita
experimental part, p. 6354 - 6363 (2010/01/06)
The reduction of the carbon-nitrogen double bond is an important transformation. Here we report our studies on a family of chiral organic catalysts able to promote the stereoselective reduction of ketimines with trichlorosilane. The very cheap, metal-free catalysts were easily prepared in one step from commercially available products, namely a chiral aminoalcohol and picolinic acid derivatives. The catalyst structure was extensively modified in a study that allowed to identify an extremely active species, able to promote the reduction on a large variety of substrates with high efficiency (up to 95% ee). A three component methodology has been also developed, where the enantiomerically enriched amine was isolated after performing the reaction by mixing a ketone and an amine in the presence of trichlorosilane and the catalyst. Its synthetic potentiality was demonstrated by employing the present metal-free catalytic procedure in the preparation of (S)-metolachlor, a potent and widely used herbicide.
A PROCESS FOR THE PREPARATION OF R-(-)-N, α-DIMETHYLPHENETHYLAMINE (LEVMETAMFETAMINE) OR S-(+)-N, α-DIMETHYLPHENETHYLAMINE (METHAMPHETAMINE) FROM d-EPHEDRINE OR L-EPHEDRINE RESPECTIVELY
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Page/Page column 20-21, (2008/06/13)
A process for synthesis of R-(-)-N, α -Dimethylphenethylamine (Levmetamfetamine, formula I), or S-(+)-N, α - Dimethyl phenethylamine (Methamphetamine, formula II ), from d-ephedrine of formula III or l-ephedrine formula IV, the process comprising the steps of (a) acylating the d- or l-ephedrine base of formula III or formula IV with an acylating agent to make a reaction mixture containing a N- acylated ephedrines of formula V or formula VI ; (b) deoxygenation of N-acylated ephedrines to make the compound of the formula VII or Formula VIII by using Raney Nickel catalyst ; and (c) acid hydrolysis of the above deoxygenated products to get the levmetamfetamine or methamphetamine.
Diastereoselective Preparation of Chiral Lithiated Allyl Amines: Application in EPC-Synthesis
Yus, Miguel,Foubelo, Francisco,Falvello, Larry R.
, p. 2081 - 2092 (2007/10/03)
Lithiation of chiral allylamine (R)-1 with BunLi and ButLi leads to the formation of intermediate (R)-2, which by reaction with D2O, Me2CO or (CH2)5CO affords the expected chiral compounds (R)-3, (R)-4 and (R)-5, respectively.With Bu
