Improved syntheses of meso-aryl tetrabenzotriazaporphyrins (TBTAPs)

New tetrabenzotriazaporphyrins are reported that are functionalised at the meso-position. The derivatives functionalised with meso-bromophenyl substituents are synthesised using an improved variation on the traditional reaction between phthalonitriles and Grignard reagents. For all other new derivatives, a modern protocol is employed that gives convenient access to these challenging materials by template co-macrocyclisation between phthalonitriles and aryl-aminoisoindoline derivatives like 15. The newly developed procedure allows design and synthesis of elaborate, functional composites and this is demonstrated by synthesis of meso-pyrenylTBTAP 24, a linked double chromophore in which the two complementary units lie perpendicular to each other and therefore have minimal ground state interaction.