| Autor: |
Cantón-Díaz AM; Universidad Autónoma de Nuevo León, Facultad de Ciencias Químicas, Ciudad Universitaria, Av. Universidad s/n. C. P. 66451, Nuevo León, Mexico. victor.jimenezpr@uanl.edu.mx., Muñoz-Flores BM; Universidad Autónoma de Nuevo León, Facultad de Ciencias Químicas, Ciudad Universitaria, Av. Universidad s/n. C. P. 66451, Nuevo León, Mexico. victor.jimenezpr@uanl.edu.mx., Macías-Gamboa LF; Universidad Autónoma de Nuevo León, Facultad de Ciencias Químicas, Ciudad Universitaria, Av. Universidad s/n. C. P. 66451, Nuevo León, Mexico. victor.jimenezpr@uanl.edu.mx., Moggio I; Centro de Investigación en Química Aplicada, Boulevard Enrique Reyna 140, 25294 Saltillo, Coahuila, Mexico., Arias E; Centro de Investigación en Química Aplicada, Boulevard Enrique Reyna 140, 25294 Saltillo, Coahuila, Mexico., Turlakov G; Centro de Investigación en Química Aplicada, Boulevard Enrique Reyna 140, 25294 Saltillo, Coahuila, Mexico., Dias HVR; Department of Chemistry and Biochemistry, The University of Texas at Arlington, Arlington, Texas, 76019-0065, USA., Colombo G; Dipartimento di Scienza e Alta Tecnologia, Università degli Studi dell'Insubria and CIRCC, Via Valleggio, 9, 22100, Como, Italy., Brenna S; Dipartimento di Scienza e Alta Tecnologia, Università degli Studi dell'Insubria and CIRCC, Via Valleggio, 9, 22100, Como, Italy., Jiménez-Pérez VM; Universidad Autónoma de Nuevo León, Facultad de Ciencias Químicas, Ciudad Universitaria, Av. Universidad s/n. C. P. 66451, Nuevo León, Mexico. victor.jimenezpr@uanl.edu.mx. |
| Abstrakt: |
Fluorescent organotin compounds are useful in sensing, optoelectronic devices, and in vitro bioimaging. Although in vitro fluorescence bioimaging shows low resolution at room temperature, a better resolution is possible at cryotemperatures. Therefore, the search for new cryoluminescent materials with potential application in high-resolution fluorescence bioimaging remains a great challenge. Herein, we report the cryoluminescence properties of two fluorescent bis-organotin compounds, namely, BisNTHySnBu 2 (5) and BisNTHySnPh 2 (6), synthesized via microwave irradiation. All compounds were fully characterized using 1 H, 13 C, and 119 Sn NMR spectroscopy, Raman spectroscopy, IR spectroscopy, and HR-MS. The 119 Sn δ and 3 J ( 1 H, 119 Sn) of 5 and 6 indicate that two Sn-ligands are chemically and electronically equivalent, as confirmed by cyclic voltammetry. The crystal structure of 6 showed pentacoordinate tin atoms with skeleton ligands. The study of self-assembled monolayers of both Sn-complexes via STM microscopy revealed a similar supramolecular packing in lamella-like patterns, adopting a face-on arrangement, where molecules stay flat lying on HOPG in accordance with the height profile of closely packed monolayers on graphite of about 0.33 nm thickness. However, only the Sn complex 6, which bears phenyls, covers large surface areas. The photophysical properties of bis-organotin compounds were also investigated in solution (room and low temperatures) and in the solid state. Good luminescence properties in solutions with fluorescence quantum yields ( Φ ) of approximately 35% and 50% were found. Despite this, Φ is quenched in the solid state because of aggregation, as supported by solvent/non solvent fluorescence studies, which is in agreement with STM and AFM investigation. |
