Synthesis and Semiconducting Characteristics of the BF Complexes of Bisbenzothiophene-Fused Azadipyrromethenes.

A novel type of dibenzothiophene []-fused core-expanded azaBODIPYs were obtained through an efficient post-functionalization of tetrabrominated azadipyrromethenes, using CuI-catalyzed cyclization, followed by BF complexation. These dyes show nearly planar skeletons, strong NIR absorption with maximum peaks up to 733 nm, and remarkable low-lying LUMO level of -4.15 eV. The field-effect transistor based on exhibits bipolar transport properties, with the highest electron and hole mobilities up to 0.012 and 0.046 cm V s, respectively.