Stereodivergent Allylic Substitutions with Aryl Acetic Acid Esters by Synergistic Iridium and Lewis Base Catalysis

Stereodivergent Allylic Substitutions with Aryl Acetic Acid Esters by Synergistic Iridium and Lewis Base Catalysis

J. Am. Chem. Soc.  2017139,  87–90.

Preparation of all possible stereoisomers of a given chiral molecule bearing multiple stereocenters by a simple and unified method is a significant challenge in asymmetric catalysis. Herein we report stereodivergent allylic substitutions with aryl acetic acid esters catalyzed synergistically by a metallacyclic iridium complexand benzotetramisole. Through permutations of enantiomers of two chiral catalysts, all four stereoisomers of the products bearing two adjacent stereocenters are accessible with high diastereoselectivity and enantioselectivity. The resulting chiral activated ester products can be converted readily to enantioenriched amides, unactivated esters, and carboxylic acids in a one-pot manner. Read more on publisher's site.