Chiral Bis(N-sulfonylamino)phosphine- and TADDOL-Phosphite-Oxazoline Ligands: Synthesis and Application in Asymmetric Catalysis
作者:Robert Hilgraf、Andreas Pfaltz
DOI:10.1002/adsc.200404168
日期:2005.1
has been prepared, containing a chiral oxazoline ring and as a second chiral unit a bis(N-sulfonylamino)phosphine group embedded in a diazaphospholidine ring or a cyclic phosphite group derived from TADDOL. These modular ligands are readily synthesized from chiral amino alcohols and chiral 1,2-diamines or TADDOLs. Palladium and iridium complexes derived from these ligands were found to be efficient catalysts
A modular synthesis of cyclohexenones is described and applied to the first enantioselectivetotalsyntheses of (+)-crypto- and (+)-infectocaryone. Key steps in the synthesis of cyclohexenones are an iridium-catalyzed allylic alkylation, nucleophilic allylation, and ring-closing metathesis. On the way to (+)-cryptocaryone, a catch and release strategy involving an iodolactonization/elimination and