Donor-Acceptor-Donor Thienopyrazines via Pd-Catalyzed C-H Activation as NIR Fluorescent Materials

作者：McNamara Louis E; Liyanage Nalaka; Peddapuram Adithya; Murphy J Scott; Delcamp Jared H; Hammer Nathan I

来源：Journal of Organic Chemistry, 2016, 81(1): 32-42.

DOI：10.1021/acs.joc.5b01958

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 phi = >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.

• 出版日期2016-1-1