Highly efficient alkene epoxidation and aziridination catalyzed by iron(II) salt + 4,4′,4″-trichloro-2,2′:6′,2″-terpyridine/ 4,4″-dichloro-4′-O-PEG-OCH 3-2,2′:6′,2″- terpyridine

Abstract

(Chemical Equation Presented) "Iron(II) salt + 4,4′,4″- trichloro-2,2′:6′,2″-terpyridine" is an effective catalyst for epoxidation and aziridination of alkenes and intramolecular amidation of sulfamate esters. The epoxidation of allylic-substituted cycloalkenes achieved excellent diastereoselectivities up to 90%. ESI-MS results supported the formation of iron-oxo and -imido intermediates. Derivitization of Cl 3terpy to O-PEG-OCH 3-Cl 2terpy renders the terpyridine unit to be recyclable, and the "iron(II) salt + 4,4″-dichloro-4′-O-PEG-OCH3-2,2′:6′,2″- terpyridine" protocol can be reused without a significant loss of catalytic activity in the alkene epoxidation. © 2008 American Chemical Society.