Journal of the American Chemical Society, Vol.139, No.16, 5787-5792, 2017
Triphosphasumanene Trisulfide: High Out-of-Plane Anisotropy and Janus-Type pi-Surfaces
A triphosphasumanene trisulfide was designed and synthesized as an out-of-plane anisotropic pi-conjugated molecule. Incorporating three anisotropic phosphine sulfide moieties into a sumanene skeleton induced a cumulative anisotropy with a large dipole moment (12.0 D), which is aligned in perpendicular direction with respect to the pi-framework and more than twice as large as those of conventional out of-plane anisotropic molecules. In the crystal, the molecules align to form columnar structures, in which electron-rich and electron-deficient sides of the pi-framework face each other. The interactions between the electron-rich surfaces, which contain three sulfur atoms, and Au(111) were examined by X-ray photoelectron spectroscopy.