Synthesis and acid-responsive spectral properties of near-infrared-absorbing donor-π-donor-type aza boron dipyrromethenes
Publication in refereed journal


摘要A series of novel near-infrared-absorbing aza boron dipyrromethenes (aza-BODIPYs) substituted with two electron-donating 4-(dimethylamino)phenylethynyl or 4-(diphenylamino)phenylethynyl groups at the 2- and 6-positions have been synthesized by palladium-catalyzed Sonogashira cross-coupling reactions. It has been found that the introduction of two dodecyloxy chains to the aza-BODIPY skeleton results in improved yield of the coupled products. These compounds have been fully characterized with various spectroscopic methods and elemental analysis. They display a strong Q-band absorption in the near-infrared region (up to 830 nm) and negligible fluorescence emission in toluene. Spectroscopic titration has also been performed for a dimethylamino derivative in chloroform. Upon addition of trifluoroacetic acid, which protonates the amino moieties, the compound shows remarkable ratiometric spectral changes. The Q-band absorption is blue-shifted from 830 to 736 nm and a new fluorescence emission at 756 nm appears, which can be attributed to inhibition of intramolecular charge transfer arising from the amino moieties. The color change from sky-blue to purple can be easily observed by direct visualization.
著者Wen-Jing Shi, Pui-Chi Lo, Dennis K.P. Ng
期刊名稱Dyes and Pigments
頁次314 - 319
關鍵詞Aza boron dipyrrometheneNear-infraredDonor-π-donorRatiometric

上次更新時間 2021-29-11 於 23:25