McNamara Louis E, Liyanage Nalaka, Peddapuram Adithya, Murphy J Scott, Delcamp Jared H, Hammer Nathan I
Department of Chemistry and Biochemistry, University of Mississippi , University, Mississippi 38677, United States.
J Org Chem. 2016 Jan 4;81(1):32-42. doi: 10.1021/acs.joc.5b01958. Epub 2015 Dec 11.
A series of thienopyrazine-based donor-acceptor-donor (D-A-D) near-infrared (NIR) fluorescent compounds were synthesized through a rapid, palladium-catalyzed C-H activation route. The dyes were studied through computational analysis, electrochemical properties analysis, and characterization of their photophysical properties. Large Stokes shifts of approximately 175 nm were observed, which led to near-infrared emission. Computational evaluation shows that the origin of this large Stokes shift is a significant molecular reorganization particularly about the D-A bond. The series exhibits quantum yields of up to φ = >4%, with emission maxima ranging from 725 to 820 nm. The emission is strong in solution, in thin films, and also in isolation at the single-molecule level. Their stable emission at the single-molecule level makes these compounds good candidates for single-molecule photon sources in the near-infrared.
通过快速的钯催化C-H活化路线合成了一系列基于噻吩并吡嗪的供体-受体-供体（D-A-D）近红外（NIR）荧光化合物。通过计算分析、电化学性质分析及其光物理性质表征对这些染料进行了研究。观察到约175 nm的大斯托克斯位移，这导致了近红外发射。计算评估表明，这种大斯托克斯位移的起源是特别是关于D-A键的显著分子重排。该系列的量子产率高达φ =>4%，发射最大值范围为725至820 nm。在溶液、薄膜中以及在单分子水平下单独存在时，其发射都很强。它们在单分子水平下的稳定发射使这些化合物成为近红外单分子光子源的良好候选者。
