On the fly multi-modal observation of ligand synthesis and complexation of Cu complexes in flow with ‘benchtop’ NMR and mass spectrometry

Abstract

Exploring complex chemical systems requires reproducible and controllable ways to access non-equilibrium conditions. Herein we present a programmable flow system that can do both ligand synthesis and complexation on the fly, and the conditions of the reaction can be monitored using two simultaneous techniques, namely NMR and mass spectrometry. By using this approach we monitored the formation of unknown complexes, followed by crystallization that resulted in the characterisation of their structures giving 5 new compounds (4 isolated and fully characterised) which can be formulated as: Cu₂(L¹)₄(μ-CO₃)](BF₄)₂ (2); [Cu₃(L¹)₆(μ-CO₃)](PF₆)₂(OH)₂ (3) [Cu₂(L²)₂](BF₄)₂ (4) and [Cu(L²)₂](BF₄)₂·CH₃CN (5).