170305-71-2Relevant academic research and scientific papers
Diastereoselective Side-Chain Alkylation of (Prolinolylmethyl)oxazoles and -oxadiazoles
Pohl, Martin,Thieme, Marion,Jones, Peter G.,Liebscher, Juergen
, p. 1539 - 1546 (2007/10/02)
Diastereoselective alkylation of the α-position of (S)-(prolinolylmethyl)oxazoles and -oxadiazoles 1 leading to side-chain modified products 2 and 3 was achieved by reaction with LDA and alkylating agents or aldehydes.The products 2 and 3 are precursors of non-natural chiral α-amino acids.The influence of substituents, reagents, and reaction conditions on the diastereoselectivity of the alkylation was investigated.A model was proposed explaining the stereochemical outcome of the reaction.Corresponding α-acylation of prolinolylmethyl heterocycles 1 with chloroformates affording chiral α-amino esters 4 were not stereoselective. - Key words: Asymmetric synthesis / Oxadiazoles / Oxazoles / Proline derivatives
