Complex selection determine phases of ~1H and ~(19)F MR signals in SABRE-based hyperpolarization

摘要

Signal Amplification By Reversible Exchange (SABRE) can be used to increase MR signals for molecular imaging.~(1, 2) The mechanism of polarization transfer to heteronuclei is currently not fully understood.~3 Information concerning chemical shifts and more important scalar couplings are significant to estimate achievable signal enhancements and their signs. Here, we take a focus on a metal complex that is necessary for SABRE. In recent years, several Ir-based complexes were examined. Two of them are the Crabtree's catalyst ([Ir(COD)(PCy3)(py)]PF_6) and the [IrIMesCODCl] complex. The selection of the complex can lead to completely different phases of the detectable signals. This will be demonstrated here in different ~1H and ~(19)F spectra.