Asymmetric epoxidation using iminium salt organocatalysts featuring dynamically controlled atropoisomerism.
Introduction of a pseudoaxial substituent at a stereogenic center adjacent to the nitrogen atom in binaphthyl- and biphenyl-derived azepinium salt organocatalysts affords improved enantioselectivities and yields in the epoxidation of unfunctionalized alkenes. In the biphenyl-derived catalysts, the atropoisomerism at the biphenyl axis is controlled by the interaction of this substituent with the chiral substituent at nitrogen.
School of Chemistry, University of East Anglia, Norwich Research Park, Norwich, Norfolk NR4 7TJ, UK. p.page@uea.ac.uk
Philip C Bulman
PC
Page
Christopher J
CJ
Bartlett
Yohan
Y
Chan
David
D
Day
Phillip
P
Parker
Benjamin R
BR
Buckley
Geracimos A
GA
Rassias
Alexandra M Z
AM
Slawin
Steven M
SM
Allin
Jérôme
J
Lacour
André
A
Pinto
D000475:Alkenes / Q000737:chemistry; D002384:Catalysis; D018360:Crystallography, X-Ray; D004852:Epoxy Compounds / Q000138:chemical synthesis* / Q000737:chemistry; D007097:Imines / Q000737:chemistry*; D008958:Models, Molecular; D015394:Molecular Structure; D012492:Salts / Q000737:chemistry; D013237:Stereoisomerism; D013816:Thermodynamics
D000475:Alkenes; D004852:Epoxy Compounds; D007097:Imines; D012492:Salts