Alkylene-Chain Effect on Microwire Growth and Crystal Packing of π-Moieties

We developed a facile approach to modulate molecular arrangement through dimerizing of π-moieties and tuning alkylene-bridge length. Dimers of fluoranthene-fused imide (DFAI-Cns) with various lengths of alkylene chains were synthesized by a Diels–Alder reaction followed by decarbonylation. DFAI-C3 and DFAI-C5 with odd-carbon alkylene chains display stronger one-dimensional growing tendency and better crystallinity than those with even-carbon alkylene chains. Microwires of dimers with odd-carbon alkylene chains were successfully obtained, and their molecular packing was analyzed by transmission electron microscopy (TEM) and selected-area electron diffraction (SAED). Systematic investigation of their single crystal packing showed that alkylene chains with different lengths produced two kinds of molecular configurations. The V-shaped molecular configuration was observed from DFAI-C3 and DFAI-C5 with odd-carbon alkylene chains; however, the Z-shaped one was observed from DFAI-C4, DFAI-C6, and DFAI-C12 with ev...