Building on the thioxanthone scaffold six years later, the group further enhanced it's reactivity by combining this photocatalyst with a different hydrogen-bonding motif in the form of chiral phosphoric acids to yield novel bifunctional catalysts TX-PA1 and TX-PA2 (Scheme 2C). Shortly thereafter, the group of Masson independently reported the synthesis of TX-PA2 and its monosubstituted C1symmetric-derivate featuring only one thioxanthone moiety. The utility of TX-PA1 to promote enantioselective processes was demonstrated in a [2+2] intermolecular cycloaddition reaction with βcarboxyl-substituted cyclic enones. The chiral phosphoric acid moiety binds to the carboxylic acid by means of two hydrogen bonds, allowing for the transference of chirality, while the attached thioxanthone moieties induce the energy transfer process. Enantiomeric ratios of up to 93:7 were achieved, albeit with only a relatively small substrate scope and with overall low yields. Despite the achievements of bifunctional thioxanthone-based catalysts in the field of enantioselective photocatalysis, 11 the ability to further modifying the thioxanthone photocatalyst core of these chiral catalysts has proven limited and modifications are usually focusing on the attached chiral backbone, and not the photocatalyst itself. This has so far restricted the ability to address limitations resulting from the photophysical properties of these chiral thioxanthone-photocatalysts, such as unmatched redox potentials or insufficient triplet energies. For example, in the case of TX-PA1, the authors noted that the triplet energy of this modified thioxanthone was significantly lowered as compared to the parent thioxanthone thioxanthen-9-one (from 272 kJ/mol to 235 kJ/mol). This need for bifunctional phosphoric acid photocatalysts with more readily tuned photophysical properties inspired us to think about alternative catalyst structures that would allow for increased design flexibility. Specifically, we were interested in the introduction of well-known donor-acceptor cyanoarene-based photocatalysts into the backbone of chiral phosphoric acids. We were especially attracted to this family of photocatalysts because of their extensively studied photophysical properties and their known understanding of how structural changes result in a tuning of these properties. This tuning is achieved by changing the donors and acceptors, which in turn change the charge transfer characteristics of the catalyst and therefore their redox and photophysical properties. Within this wide class of carbazole-based photocatalysts, we were particularly excited by the inexpensive organic dye 4CzIPN which has found tremendous applications in photocatalysis since its introduction in 2012 originally in the context of OLED research. The widespread adoption of this catalyst is due to its promising photophysical properties, including a high photoluminescence quantum yield (up to 94.6%) and a long lifetime in the excited state. Additionally, the wide redox potential window that is comparable to that of commonly utilized Ru-and Ir-polypyridyl catalysts combined with a high chemical stability make this system a particularly robust catalyst choice. Furthermore, carbazolebased photocatalysts have found utility as both effective photoredox catalysts as well as highly efficient energy transfer catalysts. On the basis of these promising features, we hypothesized that novel chiral catalysts derived from the union of chiral phosphoric acids and donor-acceptor cyanoarene-based photocatalysts would open new chemical space in both enantioselective visible light-mediated photoredox and energy transfer catalysis.