70218-55-2Relevant academic research and scientific papers
Synthesis of chiral primary amines: diastereoselective alkylation of N-[(1E)-alkylidene]-3,5-bis[(1S)-1-methoxyethyl]-4H-1,2,4-triazol-4-amin es and N4-Nexocyclic bond cleavage in the resulting 1,2,4-triazol-4-alkylamines
Serradeil-Albalat, Muriel,Roussel, Christian,Vanthuyne, Nicolas,Vallejos, Jean-Claude,Wilhelm, Didier
experimental part, p. 2682 - 2692 (2009/04/07)
Enantiomerically pure 3,5-bis[(1S)-1-methoxyethyl]-4H-1,2,4-triazol-4-amine 14a and 3,5-bis[(1S)-1-ethoxyethyl]-4H-1,2,4-triazol-4-amine 14b were used as chiral auxiliaries to obtain enantiomerically enriched α-aminoacetals, primary alkyl and arylalkyl amines (ee ranging from 40% to 90%). The different stages of the process were imine formation from the corresponding aldehydes, diastereoselective addition of a Grignard reagent, quaternization of the triazole auxiliary and cleavage of the N4-Nexocyclic bond by LiBH4. The mechanism of the cleavage of the N4-Nexocyclic bond is supported by the use of deuterated metal hydride. The absolute configurations of the new stereogenic centres were established by X-ray analyses of the enantiomerically pure stereomers isolated by semi-preparative liquid chromatography on a chiral support.
