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2,3,7,8,12,13,17,18-Octabromo-5-(2-nitrophenyl)-10,15,20-triphenyl porphyrin (H${}_{\mathrm{\text{2}}}$OBP-NO${}_{\mathrm{\text{2}}})$ and its metallic complexes have been designed and synthesized. Both the free-base porphyrin and its iron(III) complex have been characterized by X-ray crystallography. Structures confirm there are three phenyl groups and one 2-nitrophenyl at meso positions and eight bromine atoms at $\beta$-pyrrole positions. The crowded substituents cause the porphyrin plane to be distorted and become saddle shaped. The complexes were also characterized by NMR and UV-vis spectra. The UV-vis spectrum of the free-base porphyrin shows that substitution by eight bromine atoms at $\beta$-pyrrole positions leads to a red shift of the bands.

Boron subphthalocyanines (BsubPcs) are versatile molecules with advantageous properties for applications. The BsubPcs are synthesized by the cyclotrimerization of a phthalonitrile and are composed of three isoindole subunits bound by three aza-/imine-bridging nitrogens. There are a variety of BsubPc derivatives shown within the literature due to the differentiation of a phthalonitrile precursor. The differentiation of a phthalonitrile enables the peripheral functional groups. The BsubPcs can be derivatized in two steps: First step is the cyclotrimerization of a phthalonitrile in the presence of a strong Lewis Acid, typically a boron trihalide (BX3) and enables a remaining axial substituent that is a B-X${}_a$ bond; second step is optional, the B-X${}_a$ bond can react with a nucleophile and results in B-X${}_b$. If the starting phthalonitrile is asymmetric, it will result in a combination of isomers. For this study, our approach is to have bromine substituents and to study their physical properties to see if applicable to organic electronic applications; chlorine and fluorine have been in past studies as halogens are unique and variations may present useful tools as they are known for electronegativities. The general phthalonitrile with no substitutions is produced in industry from $o$-xylene. There are a variety of ways to synthesize other phthalonitriles with halogens. However, phthalonitriles can also be made by a method that has the most versatility with its substituents and can start with phthalic acid and go to phthalic anhydride to phthalimide to phthalamide and final to phthalonitrile; it is also possible to synthesize a phthalimide directly from phthalic acid, and this is part of this study as we were focusing on bromination, we also wanted to optimize the synthetic pathways to brominated phthalonitriles, and we took an engineering perspective and for this study, we wish to show you.