Max Planck Institute for Polymer Research , Ackermannweg 10, 55128 Mainz, Germany.
Empa, Swiss Federal Laboratories for Materials Science and Technology , 8600 Dübendorf, Switzerland.
J Am Chem Soc. 2017 Apr 5;139(13):4671-4674. doi: 10.1021/jacs.7b02258. Epub 2017 Mar 27.
We report on the surface-assisted synthesis and spectroscopic characterization of the hitherto longest periacene analogue with oxygen-boron-oxygen (OBO) segments along the zigzag edges, that is, a heteroatom-doped perihexacene 1. Surface-catalyzed cyclodehydrogenation successfully transformed the double helicene precursor 2, i.e., 12a,26a-dibora-12,13,26,27-tetraoxa-benzo[1,2,3-hi:4,5,6-h'i']dihexacene, into the planar perihexacene analogue 1, which was visualized by scanning tunneling microscopy and noncontact atomic force microscopy. X-ray photoelectron spectroscopy, Raman spectroscopy, together with theoretical modeling, on both precursor 2 and product 1, provided further insights into the cyclodehydrogenation process. Moreover, the nonplanar precursor 2 underwent a conformational change upon adsorption on surfaces, and one-dimensional self-assembled superstructures were observed for both 2 and 1 due to the presence of OBO units along the zigzag edges.
我们报告了迄今最长的具有沿锯齿边缘的氧-硼-氧（OBO）片段的peri 烯类似物的表面辅助合成和光谱表征，即杂原子掺杂的perihexacene 1。表面催化的环脱氢成功地将双螺旋前体 2，即 12a，26a-二硼-12，13，26，27-四氧代苯并[1,2,3-hi：4,5,6-h'i']二己烯，转化为平面 perihexacene 类似物 1，这通过扫描隧道显微镜和非接触原子力显微镜得到了可视化。X 射线光电子能谱、拉曼光谱以及对前体 2 和产物 1 的理论建模，进一步深入了解了环脱氢过程。此外，非平面前体 2 在吸附于表面时发生构象变化，由于锯齿边缘存在 OBO 单元，2 和 1 都观察到一维自组装超结构。
