2.4 Nuclear Magnetic Resonance Spectroscopy (NMR) H NMR spectra were measured with an Avance III 500 MHz spectrometer from Bruker Biospin (Ettlingen, Germany) at a temperature of 25 °C (298 K). The spectra were calibrated on the solvent signal of CD2Cl2 (5.32 ppm). Solid state C CPMAS NMR spectra were obtained with an Avance III 500 MHz spectrometer from Bruker Biospin (Ettlingen, Germany) using a double resonance CPMAS probe head. Samples were packed into 4 mm o.d. ZrO2 rotors, plugged with KEL-F endcaps and spun at spinning frequency of 12 kHz. The length of the contact time for cross-polarization was 2 ms and the cross-polarization amplitude was linearly ramped from 70% to maximum amplitude. During the acquisition the protons were decoupled using SPINAL-64 decoupling. At least 2048 scans were collected with a 5 s relaxation delay and the spectra were externally referenced to adamantane.