Copper(i)–triazole dimer formation and rate acceleration in in-source click reaction

Abstract

Besides analytical applications, ambient mass spectrometry (MS) is also a special platform to execute various chemical reactions. Chemistry in laser desorption-based, ambient MS ion sources has unique features. Previously, laser-ablated copper(I) ions were used to catalyze in-source click reactions. The advances of such in-source reaction are presented here. First, the encounter and structure elucidation of a copper(I) triazole dimer are demonstrated. Then, based on the quick appearance of such dimer in the HALDI-MS spectrum, the rate acceleration effect is studied. Last, the crystalized dimer is used to catalyze the in-flask click reaction, and confirms the proposed “di-nuclear mechanism” of the click reaction. This work is another example of how ambient in-source chemistry having unique features compares with traditional in-flask chemistry, and also shows that new insightful information can be obtained from results of ambient in-source reactions.