Coinage metal based optical small molecule sensors.

摘要

Herein the design and investigation of biologically-inspired luminescent gas sensor systems is described. This goal was achieved using a two pronged approach. The first was to design a sensor specifically for a very elusive, but important analyte, C2H4. The second involved the investigation of spectroscopic properties of a novel lumophore, [bis(2,9-di- tert-butyl-1,10-phenanthroline)Cu]B(C6F5) 4 (1), to explore its optical properties and reactivity with an eye towards determining its suitability for sensing applications.; C2H4 is responsible for significant financial losses due to produce rotting during transportation; however, there has been little headway made in development of applicable C2H4 sensors. The goal of establishing a coinage-metal based C2H4 sensing system was pursued with Ag(I), since on the periodic table it is found directly below Cu, the metal which is proposed to be in the active site of the C2H4 sensing protein ETRI. In chapter two of this thesis, the ability of luminescent AgBF4-impregnated poly (vinylphenylketone) (PVPK) films to respond to C2H4 through a luminescence quench demonstrates the principle of C2H4 sensing with Ag(I)-impregnated polymers. The breadth of response and characteristics of the sensor system, including the source of the luminescence and the mechanism of quenching are described in chapter three, and provide the basis for further development of this class of sensors.; Chapter four describes the second aspect of this research, illuminating the photophysical attributes and the unique reactivity of 1. The optical properties of 1 stem from the alkyl substituents at the 2 and 9 positions of phenanthroline, which prevent geometric reorganization of the Td Cu(I) center to the square planar "Cu(II)*" upon excitation, minimizing non-emissive relaxation paths. The larger 2 and 9 substituent size resulted in significant improvements in lifetime and quantum yield as compared to the complex which previously incorporated ligands with the largest alkyl substituents.