Meso-substituted Porphyrin Derivatives via Palladium-Catalyzed Amination Showing Wide Range Visible Absorption: Synthesis and Photophysical Studies

Abstract

In recent years, there has been a growing interest in the design and synthesis of chromophores, which absorb in a wide region of the visible spectrum, as these constitute promising candidates for use as sensitizers in various solar energy conversion schemes. In this work, a palladium-catalyzed coupling reaction was employed in the synthesis of molecular triads in which two porphyrin or boron dipyrrin (BDP) chromophores are linked to the meso positions of a central Zn porphyrin (PZn) ring via an amino group. In the resulting conjugates, which strongly absorb over most of the visible region, the electronic properties of the constituent chromophores are largely retained while detailed emission experiments reveal the energy transfer pathways that occur in each triad.

meso-2′-Linked porphyrin–BODIPY hybrids: synthesis and efficient excitation energy transfer

“…7, the BODIPY units of hybrids all take nearly perpendicular conformation to be connected to porphyrin rings, and that may weaken the πconjugation between the directly linked chromophores. This is consistent with the results in the absorption spectra and cyclic 30 voltammogram investigations. The HOMO orbital of BDP-ZnP locates on porphyrin moiety, while the LUMO orbital distributes on BODIPY unit.…”

“…As shown in Fig. 5, for the hybrid BDP-ZnP, the excited bands occurred at about 30 426, 550, and 600 nm which can be assigned to Zn(II) porphyrin, another pronounced absorption appears at around 520 nm that should come from BODIPY. Similar phenomena were observed in the other two hybrids.…”

“…Fig. 3 shows the absorption spectra of BDP-ZnP, 2BDP-ZnP, 4BDP-ZnP, and 30 the references in CHCl 3 , the related data was summarized in Table 1. Hybrid BDP-ZnP exhibits typical porphyrin Soret band at 413 nm and Q bands at 544 and 584 nm, as well as a characteristic absorption band of BODIPY at 518 nm.…”

Synthesis and properties of meso-arylporphyrin – closo-decaborate anion conjugates

“…The rest signal that doesn't have cross-peaks in the HMBC is at 141.5 ppm and belongs to C4 An . The signal of α-carbon atoms of the pyrrole rings is shown in the spectrum as a broad line with the apex at 146.2 ppm [21] (Figure 3).…”

Efficient co-sensitization of dye-sensitized solar cells by novel porphyrin/triazine dye and tertiary aryl-amine organic dye

“…Tetrahydrofuran (THF) was freshly distilled from Na/benzophenone. 5-(4-Aminophenyl)-10,15,20-triphenyl-porphy rin H 2 [TPP-NH 2 ] [19] were prepared according to literature procedures. The synthesis of compound D is described in SI.…”