A Site-Specific Synthetic Route to Substituted Inda(box) Ligands

Org Lett. 2023 Dec 29;25(51):9108-9113. doi: 10.1021/acs.orglett.3c03369. Epub 2023 Dec 14.

Abstract

Aminoindanol-derived bis(oxazoline) ligands are widely used in metal-catalyzed transformations, but the synthesis of structural derivatives is challenging. We report the gram-scale, seven-step synthesis of five bromine-functionalized inda(box) ligands that have varied bridge substituents. The bromoinda(box) ligands undergo late-stage modification via Pd-catalyzed cross-couplings, which allows for the synthesis of twelve unique inda(box) ligands. This complementary synthetic route could enable the discovery of new asymmetric metal-catalyzed transformations through the modification of the inda(box) ligand architecture.