[2,2](5,8)Picenophanedienes: Syntheses, Structural Analyses, Molecular Dynamics, and Reversible Intramolecular Structure Conversion.

This study presents an important and efficient synthetic approach to 5,8-dibromo-2,11-dibutylpicene (), with multigram scale, which was then converted to a new series of picenophanes (-). The tub-shaped [2,2](5,8)picenophanediene with two -ethylene linkers was explored using X-ray crystallography. The tub-to-tub inversion proceed through the successive bending of the linkers and the barrier for isopropyl-substituted derivative was experimentally estimated to be 18.