Highly Efficient Enantioselective Synthesis of Chiral Sulfones by Rh-Catalyzed Asymmetric Hydrogenation

Abstract

A highly efficient and enantioselective Rh-(R,R)-f-spiroPhos complex catalyzed hydrogenation of a series of unsaturated sulfones has been developed. With Rh-(R,R)-f-spiroPhos catalyst under mild conditions, not only the asymmetric hydrogenation of both the 3,3-diaryl and exocyclic α,β-unsaturated sulfones was first realized with up to 99.9% ee but also 3-alkyl-3-aryl and benzo­[b]­thiophene-1,1-dioxides were successfully hydrogenated to the corresponding chiral sulfones with excellent enantioselectivities (up to 99.4% ee) regardless of the steric hindrance, electronic property, and geometry of the substrates. Moreover, this reaction offers a route to (S)-(+)-ar-turmerone as a spice flavor, which is an important synthetic intermediate of pharmaceuticals.

Photocatalytic three-component asymmetric sulfonylation via direct C(sp3)-H functionalization

“…Other photocatalysts (PC2-PC4) failed to catalyze this transformation (entries 8-10). In order to improve the reaction e ciency and enantioselectivity, a range of chiral ligands (L2-L11) were screened (entries [11][12][13][14][15][16][17][18][19][20]. Chiral bis(oxazoline) ligands (L2-L4) and a tridentate ligand (L5), which have been successfully used for asymmetric induction in some radical-mediated transformations, 53−56 were found to be ineffective in this photocatalytic reaction (entries 11-14), but replacement of L1 with an indane-derived BOX ligand (L6) led to a full conversion and signi cantly increased enantiomeric excess (82% ee) (entry 15).…”

Enantioconvergent and enantiodivergent catalytic hydrogenation of isomeric olefins

“…The Rh catalysis showed clear enantiodivergence in hydrogenating this class of compounds. 33 In the hydrogenation of pyridine-containing 1,1-diarylalkenes reported by Zhang, it was claimed that chelation played a critical role, since the replacement of the 2-pyridine group with other aryl groups gave no conversion. However, this chelation of the substrate did not influence the enantiodivergent outcome when geometrically pure pyridine-containing olefins were evaluated.…”

Rh-Catalyzed Highly Enantioselective Synthesis of Aliphatic Sulfonyl Fluorides

“…The Rh/binap catalyzed asymmetric addition of arylboronic acids to conjugated enones was firstly reported by Hayashi and Miyaura in 1998 (Takaya et al., 1998). This pioneering method has been rapidly developed in addition to various functional groups attached alkenes such as α,β -unsaturated esters (Duchemin and Cramer, 2019, Paquin et al., 2005a, Paquin et al., 2005b, Sakuma et al., 2000), amides (Yuan and Sigman, 2018, Wang et al., 2014, Hargrave et al., 2006, Sakuma and Miyaura, 2001, Senda et al., 2001), carbonyl (Bocknack et al., 2004, Kadam et al., 2017, Khiar et al., 2013, Moragues et al., 2015, Paquin et al., 2005a, Paquin et al., 2005b, Shintani et al., 2006, Yasukawa et al., 2015), phosphonates (Hayashi et al., 1999), imines (Cui et al., 2011, Jagt et al., 2006, Lee and Kim, 2015, Nishimura et al., 2012a, Nishimura et al., 2012b, Shintani et al., 2010, Trincado and Ellman, 2008, Wu et al., 2018), sulfonyl (Lim and Hayashi, 2015, Liu et al., 2019, Mauleon and Carretero, 2005, Nishimura et al., 2012a, Nishimura et al., 2012b, Takechi and Nishimura, 2015, Yan et al., 2019), nitro compounds (Wang et al., 2010, Hayashi et al., 2000, He et al., 2015, Miyamura et al., 2017), borylalkenes (Sasaki and Hayashi, 2010), and other electron-deficient alkenylarenes (Pattison et al., 2010, Saxena and Lam, 2011). We envision that through using Rh(I) catalyst and appropriate chiral ligand, the reaction of 2-arylethenesulfonyl fluorides with arylboronic acids would furnish a class of novel chiral molecules bearing both chiral gem-diarylmethane moiety and sulfonyl fluoride functionality (Scheme 1).…”