Sterically Demanding Unsymmetrical Diaryl‐λ3‐iodanes for Electrophilic Pentafluorophenylation and an Approach to α‐Pentafluorophenyl Carbonyl Compounds with an All‐Carbon Stereocenter

摘要

AbstractA sterically demanding unsymmetrical pentafluorophenyl-triisopropylphenyl-λ3-iodane was developed as an effective reagent for the electrophilic pentafluorophenylation of various β-keto esters and a β-keto amide. 17 examples of α-pentafluorophenylated 1,3-dicarbonyl compounds 3 having a quaternary carbon center are provided. The resulting compounds were nicely transformed into chiral α-pentafluorophenyl ketones with an all-carbon stereogenic center in high yields and high enantioselectivities using asymmetric organocatalysis (up to 98 % ee) or asymmetric metal catalysis (up to 82 % ee).