Crystal Engineering Using Polyiodide Halogen and Chalcogen Bonding to Isolate the Phenothiazinium Radical Cation and Its Rare Dimer, 10‐(3‐Phenothiazinylidene)phenothiazinium
Andrew J. Peloquin, Colin D. McMillen, Scott T. Iacono, William T. Pennington
Abstract
Abstract Utilizing facile one‐electron oxidation of 10H‐phenothiazine by molecular diiodine, the solid‐state structure of the 10H‐phenothiazinium radical cation was obtained in three cation:iodide ratios, as well as its THF and acetone solvates. Oxidation of 10H‐phenothiazine with molecular diiodine in DMSO or DMF provided the structure of the radical coupling product 10‐(3‐phenothiazinyldene)phenothiazinium, which has not been crystallographically characterized to date. The radical cations were balanced by a mixture (I 7 ) − , (I 5 ) − , (I 3 ) − , and I − anions, where a variety of chalcogen, halogen, and hydrogen bonding interactions stabilize the structures to reveal these interesting cationic species.