Kubota Yasuhiro

Biography

Kubota Yasuhiro is currently working in Gifu University, Japan. His research work is on widespread applicability of organic molecules that show strong fluorescence in the solid-state in fields such as organic light-emitting diodes, organic light-emitting field-effect transistors, solid-state dye lasers, and solid-state fluorescence sensors has fuelled ever increasing research interest in such molecules. However, fluorescent dyes that exhibit fluorescence in dilute solutions generally suffer from quenched or reduced fluorescence intensity in the solid-state because of aggregation-caused quenching (ACQ). Solid-state fluorescence of dyes requires the following factors: (1) prevention of intermolecular interactions between neighboring fluorophores, which causes fluorescence quenching. (2) restriction of intramolecular rotations. (3) conformational change of the fluorophore from a twisted conformation in solution to a planar conformation in the solid-state. (4) formation of specific fluorescent aggregations such as J-type aggregation. In light of factor (a): Introduction of bulky substituent groups into a fluorophore is an effective strategy to enhance the solid-state fluorescence by preventing intermolecular interactions, such as pai-pai interactions. Utilizing this strategy, we have reported solid-state fluorescent dyes such as pyridomethene-boron complexes, pyrazine-boron complexes, tiazole-boron complexes, and pyrimidine-boron complexes.

Research Interest

His research interest is on Organic chemistry, dye, fluorescence