The reactivity and selectivity of iridium(I) catalysed hydrogen isotope exchange (HIE) reactions can be varied by using wide range of reaction temperatures. Herein, we have done a detailed comparison study with common iridium(I) catalysts (-) which will help us to understand and optimize the approaches of either high selectivity or maximum deuterium incorporation. We have demonstrated that the temperature window for these studied iridium(I) catalysts is surprisingly very broad. This principle was further proven in some HIE reactions on complex drug molecules.
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http://dx.doi.org/10.1002/open.201900204 | DOI Listing |
Dalton Trans
January 2025
Ruđer Bošković Institute, Bijenička c. 54, HR-10000 Zagreb, Croatia.
This publication describes monodentate phosphine and oxazoline ligands attached to an amino acid ester and the application of their supramolecularly assembled rhodium(I) or iridium(I) complexes in asymmetric catalysis. The major feature of these complexes is the transmission of chirality from distant hydrogen bonded amino acids to the prochiral catalytic metal center ("backdoor induction"). The generated homoleptic and heteroleptic rhodium(I) or iridium(I) precatalysts were studied by NMR, UV-VIS and CD spectroscopy as well as X-ray single crystal diffraction.
View Article and Find Full Text PDFChemistry
August 2024
Sanofi Germany, Integrated Drug Discovery, Industriepark Höchst, G876, 65926, Frankfurt am Main, Germany.
Anal Chem
November 2023
Chemistry Department, Texas A&M University, College Station, Texas 77843, United States.
Nuclear magnetic resonance (NMR) relaxometry at a low magnetic field, in the milli-Tesla range or less, is enabled by signal enhancements through hyperpolarization. The parahydrogen-based method of signal amplification by reversible exchange (SABRE) provides large signals in a dilute liquid for the measurement of relaxation using a single-scan Carr-Purcell-Meiboom-Gill (CPMG) experiment. A comparison of relaxation rates obtained at high and low fields indicates that an otherwise dominant contribution from chemical exchange is excluded in this low-field range.
View Article and Find Full Text PDFOrg Lett
August 2023
Shanghai Engineering Research Center of Molecular Therapeutics and New Drug Development, School of Chemistry and Molecular Engineering, East China Normal University, Shanghai 200062, China.
Herein we report an iridium(I)-catalyzed atroposelective alkenylation of isoquinoline-derived heterobiaryls with terminal alkynes. In the presence of a cationic iridium(I) catalyst with ()-SEGPHOS as the chiral ligand, this atom-economical alkenylation protocol allows the rapid construction of a series of axially chiral alkenylated heterobiaryls in moderate to good yields with good to high enantioselectivities.
View Article and Find Full Text PDFChem Commun (Camb)
April 2023
LCC-CNRS, Université de Toulouse, CNRS, UPS, Toulouse, France.
A series of (NHC)(cod)Ir(I) complexes bearing NHC-carboxylate ligands were efficiently synthesized and fully characterized. Their solid-state structures confirmed the bidentate coordination mode of these LX-type NHC ligands. These unprecedented iridium(I) complexes demonstrated efficient catalytic activities in dehydrogenative directed C-H silylation of arenes, and allowed for excellent -selectivity control with aromatic silylating agents.
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