Stereoselective formation of N-acyliminium ion via chiral N,O-acetal TMS ether and its application to the synthesis of beta-amino acids.
[reaction: see text] The highly stereoselective synthesis of beta-amino acids via the chiral 4-phenyloxazolidinone-controlled linear N-acyliminium ion reaction has been achieved by employing chiral N,O-acetal TMS ethers. In addition, the mechanism of the excellent stereochemical outcome has been elucidated. The oxazolidinone auxiliary plays a dual role in stereocontrol: the E/Z geometry control of the N-acyliminium ion induced by an initial stereoselective amide reduction, leading to the chiral N,O-acetal TMS ether, and face control of the nucleophile attack in the N-acyliminium ion reaction.
D000080:Acetals / Q000737:chemistry*; D000215:Acylation; D000596:Amino Acids / Q000138:chemical synthesis*; D002412:Cations / Q000737:chemistry; D018360:Crystallography, X-Ray; D004987:Ethers / Q000737:chemistry*; D007097:Imines / Q000737:chemistry*; D015394:Molecular Structure; D023303:Oxazolidinones / Q000737:chemistry*; D013237:Stereoisomerism; D014297:Trimethylsilyl Compounds / Q000737:chemistry*
D000080:Acetals; D000596:Amino Acids; D002412:Cations; D004987:Ethers; D007097:Imines; D023303:Oxazolidinones; D014297:Trimethylsilyl Compounds