For the construction of a BODIPY-containing porous scaffold, we chose the linear ditopic diamino-BODIPY derivative BDP(NH2)2 and the tritopic COF node TFP as structure-defining building blocks (see Schemes S1,S2 and Figures S1-S4 in the SI for experimental details). BDP-TFP-COF was synthesized through the AcOH-catalyzed condensation of the two precursors under solvothermal conditions. In a sealed pressure tube under argon atmosphere, both components were reacted in a 1:1 v/v mixture of ortho-dichlorobenzene and mesitylene at 120 °C for three days. After filtration of the precipitate, the remaining starting materials and small oligomers were washed out by Soxhlet extraction with anhydrous THF for 16 hours. The solid material was further purified by solvent exchange in acetone and pentane and dried under high vacuum for four hours to unclog the pores. Pure BDP-TFP-COF was obtained as a dark red powder in 86% yield. The reversible condensation between the amino groups of BDP(NH2)2 and the aldehyde groups of TFP yields the corresponding imine bonds by means of dynamic covalent chemistry, which subsequently undergoes a fast and irreversible imino-enol keto-enamine tautomerization to achieve the β-ketoenamine linked BDP-TFP-COF (Figure ). The presence of the BODIPY subunits is also confirmed by a strong signal at -145 ppm for the BF2 units in both 19 F MAS NMR for BDP-TFP-COF and 19 F solution NMR for monomeric BDP(NH2)2 (Figure ). The combination of the linear BODIPY linkers with complementary trigonal planar nodes establishes a 2D COF with hcb topology and well-defined hexagonal pores. The crystallinity and solid-state structure of BDP-TFP-COF was analyzed by PXRD (Figure ). The occurrence of one sharp and intense reflection at 2θ = 2.40° and additional weaker reflections at 4.21°, 4.89°, 6.45° and 8.46°, which could be indexed to the 100, 110, 200, 210 and 220 planes, respectively, confirmed the formation of a highly crystalline framework. Aggregation in face-to-face arranged BODIPY supramolecular polymers is typically triggered by π-π interactions between the extended aromatic surfaces and the repulsion between boron difluoride groups, which is minimized by an antiparallel stacking arrangement of the BODIPY cores in the adjacent layers. Based on such considerations, we assumed a similar stacking motif for the BDP-TFP-COF 2D layers and the unit cell was simulated in P312 space group (no. 149) featuring an eclipsed AA-type layer stacking with hcb topology. Indeed, the experimental PXRD pattern is in excellent agreement with the simulated model, thus confirming the very high crystallinity and proposed hexagonal pore structure for were obtained (Figure ). The chemical stability was tested by immersing solid COF samples in a wide variety of solvents for 24 hours. Intriguingly, BDP-TFP-COF fully retained crystallinity after exposure to various polar and non-polar solvents, e.g., H2O, 1M HCl and 1M NaOH, thus confirming the high robustness and resistance against hydrolysis for this porous material (Figure ). SEM images of BDP-TFP-COF showed interconnected microcrystalline domains, which further assembled into sponge-like agglomerates with a size of several μm (Figure ). Furthermore, EDX spectroscopy confirmed the presence of BODIPY units with an atomic composition of C, O, F, N and B (Figure ). Thermogravimetric analysis of the COF powder demonstrated the high thermal stability up to 400 °C after an initial mass loss of 8 wt%, which is attributed to the release of solvent molecules from the pores (Figure ).