A straightforward method for post-complexation derivatizations of diastereo- and enantiomerically pure bis-cyclometalated benzoxazole and benzothiazole iridium(III) complexes is reported. Triflate- and bromine-functionalized iridium(III) complex dimers, represented as [Ir(μ-Cl)(C^N)2 ]2 , were converted to the corresponding diastereomeric complexes, represented as Ir(C^N)2 (N^O), using readily available chiral salicyloxazolines and salicylthiazolines as ancillary ligands, which are represented as N^O. The Ir(C^N)2 (N^O) complexes, formed as mixtures of diastereomers, were then resolved by flash chromatography and the diastereomerically pure complexes Ir(C^N)2 (N^O) subjected to Suzuki cross-couplings. The post-complexation cross-couplings proceed without affecting the metal-located stereocenter and hence provide post-complexation derivatized non-racemic iridium(III) complexes, which were not easily accessible with previous methods. This strategy expands the toolbox to access functionalized non-racemic iridium(III) complexes for diverse applications in the life sciences, materials sciences, and catalysis.
Keywords: Suzuki-Miyaura; chirality; cross-coupling; iridium; palladium.
© 2017 Wiley-VCH Verlag GmbH & Co. KGaA, Weinheim.