1115264-53-3Relevant academic research and scientific papers
Asymmetric 1,4-addition of oxazolones to nitroalkenes by bifunctional cinchona alkaloid thiourea organocatalysts: synthesis of α,α- disubstituted α-amino acids
Aleman, Jose,Milelli, Andrea,Cabrera, Silvia,Reyes, Efraim,Jorgensen, Karl Anker
experimental part, p. 10958 - 10966 (2009/11/30)
An easy and simple synthetic approach to optically active α,α-quaternary a-amino acids using asymmetric organocatalysis is presented. The addition of oxazolones to nitroalkenes catalyzed by thiourea cinchona derivatives provides the corresponding α,α-quaternary α-amino acid derivatives with good yields, excellent diastereoselectivities (up to 98% dr), and from moderate to good enantioselectivities (up to 92% ee). The reaction can be performed on a large scale. The optically active oxazolone-nitroalkene addition products can be opened in a one-pot reaction to the corresponding esteramide derivatives. Additional transformations are also presented, such as the synthesis of amino esters, amino acids, and transformation into 3,4-disubstituted pyrrolidin-2-ones.
