A series of novel osmaindenes 1-6 bearing different substituents (CF3 , H, I, Br, OCH3 , N(Ph)2 ) has been synthesized by nucleophilic reaction of water with the corresponding aromatic osmanaphthalyne complexes. All osmaindenes 1-6 have been characterized by elemental analysis (EA) and nuclear magnetic resonance (NMR) spectroscopy, although the low solubilities of 3 and 4 precluded the accumulation of their 13 C NMR spectra. Osmaindenes 2, 3 and 5 have also been characterized by single-crystal X-ray diffraction analysis. Subsequently, through solid-state fluorescence spectroscopy, mechanochromic studies, and powder X-ray diffraction (XRD) analysis, we found that osmaindenes 1-6 fluoresce at wavelengths in the range 500-800 nm, while also displaying reversible mechanochromic properties. The solid-state fluorescence emission of 1 after grinding extends into the near-infrared region. This research provides new insight into the design and synthesis of metallic materials with excellent mechanochromic properties.
Keywords: mechanochromic; near-infrared region osmaindenes; osmanaphthalynes.
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