Ionic liquid promotes N2 coordination to titanocene(iii) monochlorideElectronic supplementary information (ESI) available: Experiment, EPR spectra (Fig. S2 and S3), and UV-vis/NIR spectra (Fig. S3-S9, Table S1). See DOI: 10.1039/c7dt01063j

Coordination of N 2 to [(Cp 2 TiCl) 2 ] in a non-coordinating ionic liquid, Pyr 4 FAP, was studied by UV-vis/NIR and EPR spectroscopies. [(Cp 2 TiCl) 2 ] is in equilibrium between monomeric [Cp 2 TiCl] and dimeric species [(Cp 2 TiCl) 2 ]. The frozen solution EPR spectrum revealed the coordination of N 2 to [Cp 2 TiCl], suggesting that Pyr 4 FAP promotes N 2 coordination to the Ti( iii ) center. Coordination of N 2 to [(Cp 2 TiCl) 2 ] in a non-coordinating ionic liquid, Pyr 4 FAP, was studied by UV-vis/NIR and EPR spectroscopies.