Mechanochromic Wide-Spectrum Luminescence Based on a Monoboron Complex

A reversible mechanochromic luminescent material based on a simple tetrahedral monoboron complex (B-1) is described. Interestingly, in addition to amorphous powders (P), the compound could exist in three unique crystal states (A, B, and C), showing efficient green-to-red luminescent colors, which is a result of wane and wax of dual emissions of the compound. Surprisingly, one of the emissions increases significantly with increasing temperature, fully offsetting the quenching effect of temperature-assisted internal conversion process. The four states are fully interconvertible through grinding and heating, allowing color writing/painting with a single ink

Mechanochromic Wide-Spectrum Luminescence Based on a Monoboron Complex

A reversible mechanochromic luminescent material based on a simple tetrahedral monoboron complex (B-1) is described. Interestingly, in addition to amorphous powders (P), the compound could exist in three unique crystal states (A, B, and C), showing efficient green-to-red luminescent colors, which is a result of wane and wax of dual emissions of the compound. Surprisingly, one of the emissions increases significantly with increasing temperature, fully offsetting the quenching effect of temperature-assisted internal conversion process. The four states are fully interconvertible through grinding and heating, allowing color writing/painting with a single ink

Mechanochromic Wide-Spectrum Luminescence Based on a Monoboron Complex

A reversible mechanochromic luminescent material based on a simple tetrahedral monoboron complex (B-1) is described. Interestingly, in addition to amorphous powders (P), the compound could exist in three unique crystal states (A, B, and C), showing efficient green-to-red luminescent colors, which is a result of wane and wax of dual emissions of the compound. Surprisingly, one of the emissions increases significantly with increasing temperature, fully offsetting the quenching effect of temperature-assisted internal conversion process. The four states are fully interconvertible through grinding and heating, allowing color writing/painting with a single ink

Mechanochromic Wide-Spectrum Luminescence Based on a Monoboron Complex

A reversible mechanochromic luminescent material based on a simple tetrahedral monoboron complex (B-1) is described. Interestingly, in addition to amorphous powders (P), the compound could exist in three unique crystal states (A, B, and C), showing efficient green-to-red luminescent colors, which is a result of wane and wax of dual emissions of the compound. Surprisingly, one of the emissions increases significantly with increasing temperature, fully offsetting the quenching effect of temperature-assisted internal conversion process. The four states are fully interconvertible through grinding and heating, allowing color writing/painting with a single ink

“Yin and Yang” Tuned Fluorescence Sensing Behavior of Branched 1,4-Bis(phenylethynyl)benzene

Achieving high sensing performance and good photostability of fluorescent films based on adlayer construction represents a significant challenge in the area of functional fluorescent film research. A solution may be offered by “Yin and Yang”, a balance idea from Chinese philosophy, for the design of a fluorophore and the relevant assembly. Accordingly, a 1,4-bis­(phenylethynyl)­benzene (BPEB) derivative (<b>C2</b>) with two cholesteryl residues in the side chains and two glucono units in the head and tail positions was designed and synthesized. As a control, compound <b>C1</b> was also prepared. The only difference between <b>C1</b> and <b>C2</b> is that the hydroxyl groups in the glucono residues of <b>C1</b> are fully acetylated. Studies of the fluorescence behaviors of the two compounds in solution revealed that both the profile and the intensity of the fluorescence emission of the compounds, in particular <b>C2</b>, are dependent on their concentration and on the nature of solvents employed. Presence of HCl also alters the emission of the compounds in solution. On the basis of the studies, three fluorescent films were prepared, and their sensing performances to HCl in vapor state were studied. Specifically, Film 1 and Film 3 were fabricated via physical coating, separately, of <b>C2</b> and <b>C1</b> on glass plate surfaces. As another comparison, Film 2 was also fabricated with <b>C2</b> as a fluorophore but at a much lower concentration if compared to that for the preparation of Film 1. As revealed by SEM and fluorescent microscopy studies, Film 1 and Film 2 exhibit well-defined microstructures, which are spherical particles and spherical pores, respectively, while Film 3 is characterized by irregular aggregates of <b>C1</b>. Fluorescence measurements demonstrated that Film 1 and Film 3 both display an aggregation emission, of which the emission from Film 1 is supersensitive to the presence of HCl vapor (detection limit: 0.4 ppb, a lowest value reported in the literatures). For Film 3, however, its emission is insensitive to the presence of the vapor. Similarly, the emission from the nonaggregated state of <b>C2</b>, a characteristic emission of Film 2, is also insensitive to the presence of the vapor. Furthermore, the sensing process of Film 1 to the vapor is highly selective and fully reversible, which lays foundation for its real-life uses. As for <b>C2</b>, the results from solution studies and those from film studies demonstrate clearly that introduction of auxiliary structures with opposite properties onto a typical fluorophore is a good strategy to develop fluorescent supramolecular motifs with rich assembly properties and great potential of applications

High-Performance Recognition, Cell-Imaging, and Efficient Removal of Carbon Monoxide toward a Palladium-Mediated Fluorescent Sensing Platform

Novel high-performance fluorescent approaches have always significant demand for room-temperature detection of carbon monoxide (CO), which is highly toxic even at low concentration levels and is not easy to recognize due to its colorless and odorless nature. In this paper, we constructed a palladium-mediated fluorescence turn-on sensing platform (TPANN-Pd) for the recognition of CO at room temperature, revealing simultaneously quick response speed (<30 s), excellent selectivity, superior sensitivity, and low detection limit (∼160 nM for CORM-3, ∼1.7 ppb for CO vapor). Moreover, rapid detection and efficient removal (24%) from the air by naked-eye vision has been successfully realized based on TPANN-Pd supramolecular gels. Furthermore, the developed sensing platform was elucidated with low cytotoxicity and high cellular uptake, and it was successfully applied to CO imaging in living cells, providing real-time monitoring of potential CO-involved reactions in biological systems

Constitutional Dynamic Chemistry-based New Concept of Molecular Beacons for High Efficient Development of Fluorescent Probes

Inspired by the concept of constitutional dynamic chemistry, we propose a new and well-adaptable strategy for developing molecular beacon (MB)-like fluorescent probes. To demonstrate the strategy, we synthesized and used an amino group containing pyrenyl derivative of cholesterol (CP) for the construction of new fluorescent probes with EDTA and sulfuric acid. The probes as created were successfully used for <i>n</i>-hexane purity checking and Ba²⁺and Pb²⁺sensing, respectively

Modular Synthesis of Diarylalkynes and Their Efficient Conversion into Luminescent Tetraarylbutadienes

A series of electronically distinct symmetrical diarylalkynes were prepared via a general Suzuki–Miyaura cross-coupling protocol. These alkynes underwent zirconium-mediated coupling to yield zirconacycles that afford new tetraaryl-1,3-butadienes upon subsequent protonolysis; these butadienes display deep blue or green emission and represent promising building blocks for light-emitting devices. The presented synthetic pathway allows access to new libraries of molecular light emitters with tunable luminescence and considerable thermal- and photostabilities

Modular Synthesis of Diarylalkynes and Their Efficient Conversion into Luminescent Tetraarylbutadienes

A series of electronically distinct symmetrical diarylalkynes were prepared via a general Suzuki–Miyaura cross-coupling protocol. These alkynes underwent zirconium-mediated coupling to yield zirconacycles that afford new tetraaryl-1,3-butadienes upon subsequent protonolysis; these butadienes display deep blue or green emission and represent promising building blocks for light-emitting devices. The presented synthetic pathway allows access to new libraries of molecular light emitters with tunable luminescence and considerable thermal- and photostabilities