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Sterically Demanding Unsymmetrical Diaryl-?(3)-iodanes for Electrophilic Pentafluorophenylation and an Approach to ?-Pentafluorophenyl Carbonyl Compounds with an All-Carbon Stereocenter.

ABSTRACT: A sterically demanding unsymmetrical pentafluorophenyl-triisopropylphenyl-?(3)-iodane was developed as an effective reagent for the electrophilic pentafluorophenylation of various ?-keto esters and a ?-keto amide. 17 examples of ?-pentafluorophenylated 1,3-dicarbonyl compounds 3 having a quaternary carbon center are provided. The resulting compounds were nicely transformed into chiral ?-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).

SUBMITTER: Matsuzaki K

PROVIDER: S-EPMC4280821 | biostudies-other | 2014 Dec

REPOSITORIES: biostudies-other

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Sterically Demanding Unsymmetrical Diaryl-λ(3)-iodanes for Electrophilic Pentafluorophenylation and an Approach to α-Pentafluorophenyl Carbonyl Compounds with an All-Carbon Stereocenter.

Matsuzaki Kohei K Okuyama Kenta K Tokunaga Etsuko E Shiro Motoo M Shibata Norio N

ChemistryOpen 20140917 6

A sterically demanding unsymmetrical pentafluorophenyl-triisopropylphenyl-λ(3)-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 u ...[more]

PMID: 25558441

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