Crystal Structures, Reaction Rates, and Selected Physical Properties of Halo-Boronsubphthalocyanines (Halo = Fluoride, Chloride, and Bromide)

Abstract

The physical properties, including the solid state arrangement, photophysics, solubility, and electrochemical behavior of a series of halo-BsubPcs (halo = F, Cl, Br) have been measured (IUPAC name halo-(7,12:14,19-diimino-21,5-nitrilo-5H-tribenzo(c,h,m)(1,6,11)triazacyclopentadecinato)-boron(III)). We have found that across the series all are relatively similar in most regards. Exceptions include that F-BsubPc can be 5 to 25 times more soluble than Cl-BsubPc in common organic solvents. F-BsubPc was also found to be hydrolytically stable under the conditions tested, whereas Cl-BsubPc and Br-BsubPc readily hydrolyzed to form HO-BsubPc. The relative rates of reaction for the series of halo-BsubPcs under standard phenoxylation conditions have also been measured. It was found that F-BsubPc does not undergo phenoxylation, whereas Br-BsubPc showed a markedly higher reaction rate relative to Cl-BsubPc. Based on these data some assumptions can be made as to the suitability of either F-BsubPc or Br-BsubPc to be used in place of the more common Cl-BsubPc. The data indicate that F-BsubPc is a potential replacement for Cl-BsubPc in organic electronic materials whereas Br-BsubPc might be more suitable as a chemical intermediate. Comments on the synthetic methods used to produce each halo-BsubPc are also made.