Isomeric Dithienophosphepines: The Impact of Ring Fusion on Electronic and Structural Properties

• Published in: Chemistry : a European journal Vol. 26; no. 16; pp. 3474 - 3478
• Main Authors: Padberg, Kevin, Ascherl, Johannes D. R., Hampel, Frank, Kivala, Milan
• Format: Journal Article
• Language: English
• Published: WEINHEIM Wiley 18.03.2020; Wiley Subscription Services, Inc; John Wiley and Sons Inc
• Subjects: Chemistry; Chemistry, Multidisciplinary; Communication; Communications; cross-coupling; Crystallography; Functional materials; phosphepines; phosphorus heterocycles; Physical Sciences; ring fusion; Science & Technology; Spectroscopy; thiophene; ring fusion; ORGANIC-PHOTOCHEMISTRY; phosphepines; thiophene; STATE; VERSATILE SYNTHESIS; phosphorus heterocycles; TRIPHENYLPHOSPHINE; 1ST ISOLATED EXAMPLES; HETEROCYCLES; 1-BENZOHETEROEPINES; cross-coupling; PI
• ISSN: 0947-6539; 1521-3765
• DOI: 10.1002/chem.201905429

The synthesis and extensive experimental (X‐ray crystallography, UV/Vis spectroscopy, cyclic voltammetry) and theoretical (DFT calculations) characterization of two isomeric dithieno[b,f]phosphepines (DTPs) are presented herein. The relative orientation of the phosphepine and the thiophene moieties has a decisive impact on the electronic and structural properties of these compounds. Moreover, the thiophene units allow for a facile subsequent functionalization through direct Pd‐catalyzed C−H coupling, which renders DTPs highly promising building blocks for organophosphorus functional materials. Similar yet different: A series of isomeric thiophene‐fused phosphepines has been synthesized and the impact of different ring fusions on structural, photophysical, and redox properties in parent as well as π‐expanded derivatives has been studied.