One-pot synthesis of functionalized piperid-4-ones: a four-component condensation.
The one-pot synthesis of highly substituted piperid-4-ones has been achieved. Diketene is added to a tosyl imine in the presence of TiCl(4) and MeOH, followed by 1 equiv of aldehyde to generate 2,6-disubstituted nonsymmetrical piperid-4-ones as a mixture of cis-/trans-diastereomers in good yields. This mixture of diastereomers can be converted to a single 2,6- cis-diastereomer by epimerization with K(2)CO(3).
Department of Chemistry, University of York, Heslington, York, North Yorks YO10 5DD, UK. pac507@york.ac.uk
Paul A
PA
Clarke
Andrey V
AV
Zaytsev
Tyson W
TW
Morgan
Adrian C
AC
Whitwood
Claire
C
Wilson
D018360:Crystallography, X-Ray; D008958:Models, Molecular; D015394:Molecular Structure; D010881:Piperidones / Q000138:chemical synthesis* / Q000737:chemistry; D000644:Quaternary Ammonium Compounds / Q000737:chemistry; D012964:Sodium / Q000737:chemistry; D013237:Stereoisomerism
D010881:Piperidones; D000644:Quaternary Ammonium Compounds; D012964:Sodium