Photocatalyzed Diastereoselective Isomerization of Cinnamyl Chlorides to Cyclopropanes.

ABSTRACT: Endergonic isomerizations are thermodynamically unfavored processes that are difficult to realize under thermal conditions. We report a photocatalytic and diastereoselective isomerization of acyclic cinnamyl chlorides to strained cyclopropanes. Quantum mechanical calculations (uM06-2X and DLPNO), including TD-DFT calculations, and experimental studies provide evidence for the energy transfer from an iridium photocatalyst to the allylic chloride substrate followed by C-Cl homolytic cleavage. Subsequent Cl^• radical migration forms a localized triplet 1,3-diradical intermediate that, after intersystem crossing, undergoes ring-closing to form the desired product. The mild reaction conditions are compatible with a broad range of functional groups to generate chlorocyclopropanes in hi

SUBMITTER: Xu B 

PROVIDER: S-EPMC7224234 | biostudies-literature | 2020 Apr

REPOSITORIES: biostudies-literature