Synthesis and Photophysical Properties of Asymmetric Substituted Silafluorenes
摘要:
Several 1,3-diphenyl-substituted silafluorene compounds were synthesized and characterized as potential fluorescent materials for OLED fabrication and bioimaging. Introducing phenyl groups into the silafluorene ring at the land 3-positions led to a red shift in the emission, resulting in blue light emitting compounds (lambda(max) 368-375 nm in solution; lambda(max) 362-371 and 482 nm in the solid state), and improved the quantum yield efficiency both in solution and as solids. Aggregation enhanced emission of the silafluorenes (AEE) was also investigated. Theoretical MO calculations were carried out to aid in understanding the optical properties of these molecules. Since these compounds might be useful in bioimaging, their toxicity was also investigated in skin fibroblast cells. All compounds were found to be nontoxic to the investigated cell cultures.
Synthesis and High Solid-State Fluorescence of Cyclic Silole Derivatives
作者:Yuanjing Cai、Kerim Samedov、Brian S Dolinar、Zhegang Song、Ben Zhong Tang、Chaocan Zhang、Robert West
DOI:10.1021/om500884b
日期:2015.1.12
Cyclotetrasiloxanes 13 containing different silole-based fluorogenic units (silafluorene, 1,3-diphenyl-9-silafluorene, tetraphenylsilole) were synthesized by cohydrolysis and condensation reactions. Their optical properties in solution and as crystals were studied. These compounds have low quantum yields in solution (Phi(fl) = 0.01-0.18) with fluorescence maxima at 359-375 nm for silafluorene-containing compounds 1 and 3 and at 491 nm for AEE-active tetraphenylsilole compound 2. However, 13 have high solid-state quantum yields (Phi(fl) = 0.65-0.78) with fluorescence maxima at 377-390 nm for compounds 1 and 3 and at 517 nm for tetraphenylsilole- and silafluorene-containing compound 2. Packing analysis of 13 in the crystal structure and MO and excited-state calculations were performed to explore possible fluorescence mechanisms in these compounds.