262301-37-1Relevant articles and documents
Diastereoselective synthesis of β2-amino acids
Ponsinet, Rachel,Chassaing, Gérard,Vaissermann, Jacqueline,Lavielle, Solange
, p. 83 - 90 (2007/10/03)
As part of an ongoing project concerning the synthesis of nonnatural amino acids, we have now developed a general strategy for the preparation of β2-amino acids (or 2-aminocarboxylic acid derivatives). Our procedure involves the synthesis of the sultam β-alaninate precursor 5 whose alkylation led with high yields and excellent diastereoselectivity to the precursor of β2-homophenylalanine, β2-homoalanine, and β2-homoleucine. Subsequent deprotection and Boc-protection yielded the expected β2-amino acids. X-ray analysis of the alkylation product established that (-)-sultam yielded (R)-β2-amino acids, conversely (+)-sultam yielded the enantiomer. The topicity of this alkylation is in agreement with the alkylation of Oppolzer's precursor for the synthesis of α-amino acids and opposite to that observed for gem-dialkylation.
