New modes for the osmium-catalyzed oxidative cyclization.
The osmium-catalyzed oxidative cyclization of amino alcohol initiators formally derived from 1,4-dienes is an effective method for the construction of pyrrolidines, utilizing a novel reoxidant (4-nitropyridine N-oxide = NPNO). The cyclization of enantiopure syn- and anti-amino alcohols gives rise to enantiopure cis- and trans-2,5-disubstituted pyrrolidines, respectively. Moreover, the cyclization of bis-homoallylic amines bearing an exocyclic chelating group is shown to be a complementary method for trans-pyrrolidine formation.
Department of Chemistry, University of Oxford, Chemistry Research Laboratory, Mansfield Road, Oxford, OX1 3TA, United Kingdom. timothy.donohoe@chem.ox.ac.uk
Timothy J
TJ
Donohoe
Peter J
PJ
Lindsay-Scott
Jeremy S
JS
Parker
Cedric K A
CK
Callens
D002384:Catalysis; D003500:Cyclization; D008958:Models, Molecular; D008968:Molecular Conformation; D009992:Osmium / Q000737:chemistry*; D010084:Oxidation-Reduction
D009992:Osmium