RESUMEN
The synthesis and photophysical properties of cyano and ethynyl substituted carbazole-based porphyrins were investigated. The introduction of ethynyl groups induced red shifts, while that of cyano groups induced blue shifts of their absorption bands, which was supported by MO calculations. Ethylenedioxy-appended porphyrins were also prepared via a coupling reaction. The conjugated and electronic substituent effects on the photophysical properties of the carbazole-based porphyrins have been elucidated by using both experimental results and calculations. Among these porphyrins, the ethylenedioxy-appended selenaporphyrin displayed intensified and red-shifted absorption in the NIR region up to 1178 nm.
RESUMEN
Cu(I)-mediated annulation reaction of a 1,1'-(1,3-butadiyne)-8,8'-(2,5-thiophene)-bridged carbazole dimer 10 with amines provided the N-substituted carbazole-based isophlorines 11a-11c. A similar annulation reaction with selenium in the presence of hydrazine monohydrate afforded hetero-core-modified isophlorine 12. The oxidation of 12 generated the corresponding 21-selena-23-thiaporphyrin 13, which exhibited NIR absorption. The intramolecular charge transfer from Se to S was confirmed by the (1)H NMR results along with DFT calculations.
RESUMEN
Cu(I)-mediated alkoxylation of doubly 1,3-butadiyne-bridged carbazole dimer 1, followed by acid-catalyzed cyclization, provided furan-bridged carbazole dimer 3, while annulation reaction of 1 with selenium in the presence of hydrazine monohydrate provided selenophene-bridged carbazole dimer 5a. Oxidation of isophlorin 5a afforded carbazole-based selenaporphyrin 5b, which possessed distinct aromaticity and produced intensified and red-shifted absorption bands in the near-IR region.