General considerations. All experiments were performed under dry and inert (Argon) conditions in flame-or oven-dried glassware following standard Schlenk techniques or in a N2-filled glovebox, unless stated otherwise. All reagents were obtained from commercial suppliers and used without further purification, except for the compounds given below. DCM was pre-dried using a Solvent Purification System (SPS) from MBraun (MB SPS-800, with standard MBraun drying columns). All solvents were dried (further) and stored on activated 3 Å molecular sieves and degassed by sparging with argon or freeze-pump-thaw. Styrene was filtered over basic alumina and sparged with Argon before use. A Kessil PR 160L 370 nm (first generation) or 525 nm were used as light sources. 1 H NMR and 13 C NMR spectra were recorded on a Bruker DRX 500, AMX 400, or DRX 300 spectrometer at room temperature and referenced to TMS. Individual peaks are reported as: chemical shift (ppm), multiplicity (s: singlet, d: doublet, t: triplet, q: quartet, m: multiplet), integration, coupling constant (Hz). During NMR measurements with light irradiation, a Bluepoint 4 with 390-500 nm filter from Honle UV Technology was used with an optic fiber leading to the bottom of the NMR sample. EPR spectra were recorded on a Bruker EMX X-band spectrometer equipped with an ER 4112HV-CF100 He cryostat. UV-Vis spectra were recorded on a double beam Shimadzu UV-2600 spectrophotometer in a 1.0 cm quartz cuvette or a 1.0 cm Teflon screw-cap quartz cuvette with an extra 10 mL round bottom flask, using the solvent as background. Cold spray ionization mass spectrometry (CSI-MS) spectra were collected on a HR-ToF Bruker Daltonik GmbH (Bremen, Germany) Impact II, an ESI-ToF MS capable of resolution of at least 40000 FWHM, which was coupled to a Bruker cryo-spray unit. The source voltage was between 3 and 6 kV. The sample was introduced with a syringe pump at a flow rate of 180 μl/hr. The drying gas (N2) was held at and the spray gas was held at -35°C. The machine was calibrated via direct infusion of a TFA-Na solution. Software acquisition Compass 2.0 for Otof series. Field desorption (FD) mass spectra were collected on an AccuTOF GC v 4g, JMS-T100GCV Mass spectrometer (JEOL, Japan).