Coevolution and ratiometric behaviour in metal cation-driven dynamic covalent systems† †Electronic supplementary information (ESI) available. See DOI: 10.1039/c6sc04662b Click here for additional data file.

Instrumentation: NMR spectra were recorded on Bruker Advance 400 (400.14 MHz for 1H and 100.62 MHz for 13C), Bruker Advance III plus 400 (400.34 MHz for 1H and 100.67 MHz for 13C), and Bruker Advance III 600 (600.13 MHz for 1H and 150.90 MHz for 13C) NMR spectrometers. All the collected spectra were referenced on residual solvent signal according to Nudelman and coworkers.[1] Mass spectra were obtained on Bruker MicroTOF and HRMS on Bruker MicroTOFQ, both with electrospray ionization. Nominal precision of the HRMS analysis is 10 ppm.