Pure 9 was then submitted to the previously optimized conditions of the Suzuki coupling of 4; namely a solvent mixture of 1,4-dioxane, water and DMF with Cs2CO3 as base and Pd(PPh3)4 as the palladium catalyst (Scheme 6A). Surprisingly, no desired cross-coupled product 10 was observed, and only what was assigned to be the monocoupled product was obtained. We hypothesized that this lack of biscoupling may be due to the increased steric hinderance of attaching the photocatalyst moiety directly at the carbazole, rather than by an additional benzylic linker as it was the case in the synthesis for 5. As such, an alternative route was explored, allowing a stepwise introduction of the steric bulk (Scheme 6B). First, the sterically less demanding 3-bromocarbazole was submitted to a Suzuki coupling, yielding 11 in an excellent yield of 94%. We envisioned taking advantage of the reduced steric bulk surrounding the carbazole nitrogen to introduce the remainder of the photocatalyst through a nucleophilic aromatic coupling strategy. Gratifyingly, this coupling of 11 with aryl fluoride 8 was successful and produced desired intermediate 10 in 90% yield. It is noteworthy that the nucleophilic substitution leading to 10 was only achieved using NaH and not when using NaHMDS, the ladder of which is often used in the synthesis of 2CzPN or 4CzIPN. This synthetic route is also advantageous over the initially attempted route by reducing the total step count and by avoiding the need for 3 equivalents of brominated 2CzPN 9 and instead using only a minimal 0.1 equivalents excess of 8. After obtaining the desired coupled product 10, the demethylation conditions that worked well for catalyst PCI precursor 5 were applied (1 M BBr3 in DCM, 4.0 eq.). Unfortunately, these conditions only led to the decomposition of 10. Utilizing less harsh reaction conditions, such as lowering the temperature of the BBr3 reaction to -78 °C before quenching at room temperature or using AlCl3 24 in place of BBr3, also failed to give the desired product and only resulted in in the formation of decomposition products. The use of pyridinium hydrochloride neat at 200 °C was next explored but resulted in no conversion of the starting material 10. By doubling the equivalents of BBr3 from 4 to 8 at a reaction temperature of -78 °C, while also quenching the reaction mixture at this low temperature, a new compound was obtained that was identified to be monodemethylated 10. However, neither longer reaction times (1-6 h) nor more equivalents of BBr3 were able to push the reaction to complete demethylation. Finally, it was found that using trimethylsilyl iodide 26 in dry deuterated chloroform followed by quenching with methanol overnight produced the desired doubly demethylated catalyst precursor 12 in a moderate yield of 61% (Scheme 7, step 1). Targeting the formation of PCII, the free binaphthol 12 was then submitted to the same phosphorylation conditions as was used previously on 7 for the synthesis of PCI. However, in this case it is worth mentioning that the resulting 31 P-NMR showed three singlet phosphorus signals in proximity at ppm = 0.56, 0.76, 0.92 in DMSO-d6. Conformational restrictions resulting in the formation of diastereomers at phosphorus were suspected to be a potential cause of this observation. Therefore, high temperature NMR studies in DMSO were carried out. However, these experiments proved inconclusive as heating the sample to 368 K (95 °C) did not result in coalescence of the signals. Further, neither different column chromatographic purification conditions nor recrystallization led to any observable change in the ratio of the signals in the NMR spectra ( 1 H and 31 P).