Coordinating-ion-spray mass spectroscopy as a method for the detection and identification of electron-poor and air-sensitive phosphines

• Silver complexes of electron poor phosphines. • Gold complexes of very electron poor phosphines. • HRMS of gold/silver complexes. • Coordination ion spray mass spectrometry. • Comparison of programs for determination of isotopic mass. Electron-poor metal complexes play a pivotal role in catalytic cycles, influencing reactivity and reaction pathways. Despite their significance, the utilization of electron-poor phosphine ligands is limited in the literature due to their air and moisture sensitivity, complicating their full characterization. To address the analytical needs of electron-poor phosphines, coordinating-ion-spray mass spectrometry (CIS-MS) emerges as a promising tool, offering sensitivity and versatility particularly suited for challenging compounds.