Boron as a key component for new π-electron materials

For the molecular design of new pi-electron materials, the incorporation of main group elements into the pi-conjugated frameworks is a powerful approach to modifying the nature of the parent pi-conjugated systems. In particular, the group 13 boron is of interest, since the boron element has several characteristic features, such as an effective orbital interaction with the pi-conjugated frameworks through the vacant p-orbital (i.e., p(pi)-pi* conjugation), high Lewis acidity, and trigonal planar geometry. By exploiting these features of the boron atom, we have designed and synthesized several types of new pi-electron materials, including trianthrylborane- or dibenzoborole-based pi-conjugated systems as a new fluoride ion sensor, boryl-substituted thienylthiazole as a new building unit for electron-tran sporting materials, and B,B',B-trianthrylborazine (B3N3)-based materials as a model of the bundled system of pi-conjugated frameworks.