Kinetic Resolution of Sulfur-Stereogenic Sulfoximines by Pd(II)-MPAA Catalyzed C-H Arylation and Olefination
| Autor: | Majji Shankar, Akhila K. Sahoo, Vincent Gandon, Somratan Sau, Nicolas Grimblat, Kallol Mukherjee, Koushik Ghosh |
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| Rok vydání: | 2021 |
| Předmět: | |
| Zdroj: | Chemical Science |
| DOI: | 10.33774/chemrxiv-2021-2cls6 |
| Popis: | A direct Pd(ii)-catalyzed kinetic resolution of heteroaryl-enabled sulfoximines through an ortho-C–H alkenylation/arylation of arenes has been developed. The coordination of the sulfoximine pyridyl-motif and the chiral amino acid MPAA ligand to the Pd(ii)-catalyst controls the enantio-discriminating C(aryl)–H activation. This method provides access to a wide range of enantiomerically enriched unreacted aryl-pyridyl-sulfoximine precursors and C(aryl)–H alkenylation/arylation products in good yields with high enantioselectivity (up to >99% ee), and selectivity factor up to >200. The coordination preference of the directing group, ligand effect, geometry constraints, and the transient six-membered concerted-metalation–deprotonation species dictate the stereoselectivity; DFT studies validate this hypothesis. A Pd/MPAA catalysed KR of heteroaryl substituted sulfoximines through C–H alkenylation and arylation (up to >99% ee) is developed. In-depth DFT studies uncover the salient features. |
| Databáze: | OpenAIRE |
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