Catalytic asymmetric intramolecular aminopalladation: improved palladium(II) catalysts.
[reaction: see text] Cobalt oxazoline palladacyclic (COP) complex 4 containing acetate as a bridging ligand is an excellent catalyst for asymmetric intramolecular aminopalladation to synthesize 4-vinyloxazolidin-2-ones in 91-98% ee. In contrast to previously reported Pd(II) catalysts, COP-OAc (4) promotes the asymmetric cyclization of (Z)-allylic N-tosylcarbamates without prior activation by silver salts.
Kirsch
Stefan F
SF
Department of Chemistry, 516 Rowland Hall, University of California, Irvine, California 92697-2025, USA.
Overman
Larry E
LE