53940-82-2Relevant articles and documents
Enantioselective radical addition to ketimines: A synthetic route towards α,α-disubstituted α-amino acids
Kim, Sang Yoon,Kim, Sung Jun,Jang, Doo Ok
supporting information; experimental part, p. 13046 - 13048 (2011/02/21)
A radical attack: In the presence of a protonated cinchonine derivative, radical addition reactions proceeded efficiently, providing a general approach to the synthesis of a diverse range of enantioenriched α,α- disubstituted α-amino acids.
Tertiary aromatic amide for memory of chirality: Access to enantioenriched α-substituted valine
Branca, Mathieu,Gori, Didier,Guillot, Regis,Alezra, Valerie,Kouklovsky, Cyrille
, p. 5864 - 5865 (2008/09/20)
A new methodology for the asymmetric synthesis of quaternary α-substituted amino acids using memory of chirality has been developed. This strategy employs dynamic axial chirality of tertiary aromatic amides to memorize the initial chirality of an α-amino acid during the enolization step. Starting from l-valine, an oxazolidin-5-one containing a tertiary aromatic amide was synthesized in one step and then alkylated with various electrophiles with good yield and enantioselectivity (up to 96%). Quaternary products can be obtained enantiomerically pure by recrystallization. One-step deprotection affords enantioenriched (S)-α-methyl valine (ee = 94%) or enantiopure (S)-α-isopropyl aspartic acid (ee >99%) in only three steps starting from L-valine. Copyright
Chiral 2-cyano esters as synthetic intermediates in the synthesis of R and S-α-methylvaline
Cativiela,Diez-De-Villegas,Galvez,Lapena
, p. 5921 - 5928 (2007/10/02)
A divergent stereoselective synthesis of R and S α-methylvaline from (2RS) (1S,2R,4R)-10-dicyclohexylsulfamoylisobornyl 2-cyano-3-methylbutanoate has been developed.
