AI Article Synopsis
- The past century has focused mainly on the Z/E isomerization of di- and tri-substituted alkenes, leaving the tetrasubstituted isomerization largely unexplored.
- This study introduces a method for the atroposelective synthesis of tetrasubstituted alkene analogues through asymmetric allylic substitution and triplet energy transfer photocatalysis for Z/E isomerization.
- Key findings highlight that the generation and distribution of benzylic radicals are crucial for maintaining the enantioselectivities in the synthesis of axially chiral N-vinylquinolinones.
Article Abstract
The past century has witnessed a large number of reports on the Z/E isomerization of alkenes. However, the vast majority of them are still limited to the isomerization of di- and tri-substituted alkenes. The stereospecific Z/E isomerization of tetrasubstituted alkenes remains to be an underdeveloped area, thus lacking in a stereodivergent synthesis of axially chiral alkenes. Herein we report the atroposelective synthesis of tetrasubstituted alkene analogues by asymmetric allylic substitution-isomerization, followed by their Z/E isomerization via triplet energy transfer photocatalysis. In this regard, the stereodivergent synthesis of axially chiral N-vinylquinolinones is achieved efficiently. Mechanistic studies indicate that the benzylic radical generation and distribution are two key factors for preserving the enantioselectivities of axially chiral compounds.
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| http://www.ncbi.nlm.nih.gov/pmc/articles/PMC11021481 | PMC |
| http://dx.doi.org/10.1038/s41467-024-47404-3 | DOI Listing |
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