Dual Photoredox Catalysis. Metallaphotoredox catalysis is a fast growing area of research as it often offers a mild alternative to existing transition metal catalytic reactions and give access to different redox couples of the co-catalyst, resulting in new reactivity. Nickel in particular has been paired with photocatalysts for a wide range of different coupling reactions with Luo and Zhang 12 reporting the first use of 4CzIPN as a photocatalyst in a dual-mode catalyzed (C)sp 3 -(C)sp 2 cross-coupling. Employing a modified version of this reaction to assess the performance of DiKTa and Mes3DiKTa, using 4CzIPN, the coupling reaction between 1a and aryl bromide 9 gave the desired product 10 in 78% yield (Table , entry 1). Both DiKTa and Mes3DiKTa gave similar results of 78% and 72%, respectively (Table , entries 2 and 3), providing further evidence of the versatility of these two PCs. Hydrogen atom transfer (HAT) catalysts are also commonly partnered with photocatalysts and have been used for dehalogenation reactions. A recent example, reported by Constantin et al., used the alkyl radicals generated after the reductive quenching between PC* and triethylamine to abstract iodine atoms from alkyl iodides 11 to generate alkyl radicals that typically would require a far more potent reductant (Ered(R-I) < -2 V). These alkyl radicals can then be trapped by a thiol HAT catalyst to generate the dehalogenation products 12 (Table ). Under the literature conditions using 4CzIPN, an 85% yield of 12 was obtained (Table , entry 1). Both DiKTa and Mes3DiKTa were able to achieve comparable average yields of 88% and 86%, respectively (Table , entries 2 and 3). Reaction Profile and Rates Analysis. Reactions in the previous sections have used the yield of the reaction after a given time to compare the efficiency of the PCs. While useful, this provides an incomplete picture of these reaction processes as it does not allow comparison of relative rates of product formation. This prompted an investigation into the reaction kinetics of the PCs for a model transformation, with the ATRA reaction between 4a and 5 shown in Table chosen. Inspired by Yi et al. in situ NMR was used to monitor the generation of product employing each of the PCs (Figure ).