Rapid Analysis of Residual Palladium in Pharmaceutical Development Using a Catalysis-Based Fluorometric Method

Measurement of residual metals in pharmaceutical intermediates is routinely performed using inductively coupled plasma-optical emission spectroscopy (ICP-OES) or inductively coupled plasma-mass spectrometry (ICP-MS). However, these techniques suffer from drawbacks that limit their utility in pharmaceutical process development, including the requirement for expensive instrumentation, complex sample preparation, slow turnaround time, limited sample throughput, and the difficulty of performing the required measurements on the 'spot' within pilot plants or manufacturing environments. We investigate the use of a fast and inexpensive high-throughput approach for detection of residual palladium (Pd), based on the Pd-catalyzed Tsuji-Trost deallylation of an allylic ether substrate to produce a highly fluorescent product. We demonstrate the effectiveness of this fluorescence assay for accurate quantitation of Pd levels in a variety of 'real world' samples, including mixed oxidation-state samples containing strong Pd ligands.