Asymmetric Synthesis of Enantiomerically Enriched alpha-Amino Acids Containing 2-Furyl- and 2-Thienyl-1,2,4-triazoles in the Side-Chain

作者：Saghyan Ashot S; Simonyan Hayarpi M; Petrosyan Satenik G; Mkrtchyan Anna F; Khachatryan Lilit V; Geolchanyan Arpine V; Samvelyan Melanya A; Ghochikyan Tariel V; Kelzhanova Nazken; Saginayev Amanzhan T; Langer Peter^*

来源：Zeitschrift Fur Naturforschung Section B-a Journal of Chemical Sciences, 2014, 69(4): 451-460.

DOI：10.5560/ZNB.2014-3221

• Asymmetric Synthesis
• Amino Acids
• Chiral Ni-II Complexes
• Heterocycles

An efficient method for the asymmetric synthesis of alpha-amino acids, containing furyl- and thiophenyl-substituted triazoles in their side-chain, is reported. The strategy relies on Michael addition of 3,4,5-substituted 1,2,4-triazoles to the C=C bond of chiral Ni-II complexes containing the Schiff base formed from dehydroamino acids (dehydroalanine and (E + Z)-dehydroaminobutyric acid) and from chiral auxiliaries, i.e. (S)-2-N-(N%26apos;-benzylprolyl)aminobenzophenone and (S)-2-N-(N%26apos;-2-chlorobenzylprolyl) aminobenzophenone. The reactions proceeded with good to very good diastereoselectivity. Hydrolysis of the diastereomeric mixtures of metal complexes afforded the enantiomerically pure alpha-amino acids with high enantiomeric excess (ee %26gt; 98%).

• 出版日期2014-4