Designs And Syntheses Of Novel Long Wavelength, Functional Bipyrrole And Tirpyrrole Dyes

Long wavelength and NIR fluorescent dyes have importantapplications in bio-analysis and clinic research areas, since they can avoidthe background absorption, autofluorescence and light scattering toincrease the detection sensitivity, doing less damage to the biosystem andmay be applied for the in-vivo images. Several problems wereencountered with the preparation and application of the NIR fluorescentdyes, such as the aggregation, photobleaching and low fluorescencequantum yield. So it is necessary to synthesize novel and more effectivedyes that absorb and emit in the NIR region. In this thesis, we havedesigned and synthesized several series of novel long wavelengthincluding near IR fluorescence molecules as following:1. Designed and synthesized novel3,5-diiodoBODIPY1platform.At the3,5-position, BODIPY2was synthesized using Sonagashiracoupling reactions, which emitted in the near-infrared region. We alsostudied the photophysical properties of the dyes and determined thefluorescence quantum yields in different solvents.2. Designed and synthesized a novel3-halogenated benzo-fusedBODIPY3from readily available3-halogeno-1-formylisoindole, andfeatured with an active reacting site at the3-position. The application ofthis platform in Sonogashira coupling and nucleophilic substitutionreactions generates a series of asymmetrical benzo-fused BODIPY4and BODIPY5. Most of the resultant BODIPY dyes show long-wavelengthabsorption and fluorescence emission, with good fluorescence quantumyields and long fluorescence lifetimes.3. Developed a facial synthesis of BODIPY6and7. These novelBODIPY dyes showed particularly useful optical properties such as thelong-wavelength sharp absorption and fluorescence, high fluorescencequantum yields (up to0.91), and high photostability. The wavelength isfinely tuneable over a wide range (up to714nm) by simple variation ofsubstituent groups and through functionalization. The unexpected facialone-pot syntheses and the excellent photophysical properties of theseBODIPY dyes may render them potential applications in fluorescentlabelling and imaging areas.4. Developed a easily synthetic strategy for the facile preparation ofa series of prodiginines using an Lewis acid-catalyzed “one-pot” or a“two step” fashion synthetic route, which allows the preparation ofprodiginines with both the symmetrical and unsymmetricalpyrrolepyrromethene8in relatively good yields.5. Designed the regioselective formylation of BODIPY9α-formylation and synthesized BODIPY10and β-substituted BODIPY11dyes, which make contributions to the theory of the chemical reactionof BODIPY and provide facile route for the efficient functionalization ofBODIPY chromophore. The installation of formyl groups affects theelectronic properties of the BODIPY chromophore, resulting in a red-anda blue-shift of the absorption and emission maxima respectively for the α-and β-formylated BODIPYs10and BODIPYs11.