Enantioselective Bifunctional Ammonium Salt-Catalyzed Syntheses of 3-CF3S-, 3-RS-, and 3-F-Substituted Isoindolinones

We herein report the ammonium salt-catalyzed synthesis of chiral 3,3-disubstituted isoindolinones bearing a heteroatom functionality in the 3-position. A broad variety of differently substituted CF3S- and RS-derivatives were obtained with often high enantioselectivities when using Maruoka's bifunctional chiral ammonium salt catalyst. In addition, a first proof-of-concept for the racemic synthesis of the analogous F-containing products was obtained as well, giving access to one of the rare examples of a fairly stable alpha-F-alpha-amino acid derivative.

Automated summary

In this study, chiral 3,3-disubstituted isoindolinones were synthesized using ammonium salt catalysis, yielding a variety of differently substituted CF3S- and RS-derivatives with high enantioselectivities. Additionally, a racemic synthesis of F-containing products was achieved for the first time, producing a stable alpha-F-alpha-amino acid derivative.