An Approach for Highly Enantioselective Synthesis of meta-Disubstituted [ n]Paracyclophanes

J Org Chem. 2024 Oct 18;89(20):15374-15379. doi: 10.1021/acs.joc.4c02021. Epub 2024 Sep 27.

Abstract

Atroposelective synthesis of meta-disubstituted [n]paracyclophanes is a difficult task in organic chemistry. We describe a facile approach for the synthesis of meta-disubstituted [n]paracyclophanes using Pd-catalyzed enantioselective C-H olefination and sequential reductive cleavage. A wide range of [n]paracyclophanes was obtained with excellent enantioselectivity. Thermodynamic analysis revealed that the rotational barrier of meta-disubstituted [n]paracyclophanes was lower than that of para-disubstituted [n]paracyclophanes. The synthesized planar-chiral [14]paracyclophane showed a bright fluorescence emission and impressive circularly polarized luminescence activity.