Synthesis and exploration of electronically modifiedud(R)-5,5-dimethyl-(p-CF_3)_3-i-PrPHOX in palladium-catalyzedudenantio- and diastereoselective allylic alkylation: a practical alternative to (R)-(p-CF_3)_3-t-BuPHOX

摘要

The synthesis of the novel electronically modified phosphinooxazoline (PHOX) ligand, (R)-5,5-dimethyl-(p-CF_3)_3-i-PrPHOX, is described. The utility of this PHOX ligand is explored in both enantio- and diastereoselective palladium-catalyzed allylic alkylations. These investigations prove (R)-5,5-dimethyl-(p-CF_3)_3-i-PrPHOX to be an effective and cost-efficient alternative to electronically modified PHOX ligands derived from the prohibitively expensive (R)-t-leucine.