773091-81-9Relevant academic research and scientific papers
Isoxazolinium salts in asymmetric synthesis. 1. Stereoselective reduction induced by a 3′-alkoxy stereocentre. A new approach to polyfunctionalized β-amino acids
Henneb?hle, Marco,Le Roy, Pierre-Yves,Hein, Matthias,Ehrler, Rudolf,J?ger, Volker
, p. 451 - 467 (2007/10/03)
A new approach to optically active N-methylamino acids is presented, relying on stereoselective reduction of N-methylisoxazolinium salts with a dioxyethyl side-chain. The diastereoselectivity of the reduction step is studied systematically, in comparison with that of respective isoxazolines. A two-step transformation of isoxazolinium salts - with NaBH3(OAc) and subsequent catalytic hydrogenation as well as a one-pot reduction by catalytic hydrogenation led to high (95:5 and 87:13) diastereomeric ratios of protected erythro-N-methylaminopentanetriols. The hydroxyethyl side-chain is elaborated by oxidation to afford the β-N-methylamino acid 37, exemplifying the potential of this strategy.
