Meso-Fused Carbatriphyrins(2.1.1) and Its Organo Phosphorus(V) Complex

The first examples of phlorin analogues of meso-fused carbatriphyrins(2.1.1) and organo P­(V) complex of one of the meso-fused carbatriphyrins were obtained by adopting a premodification strategy starting with fluorene as a fused polyaromatic precursor over a sequence of steps. The meso-fused carbatriphyrins(2.1.1) were obtained as their nonaromatic phlorin analogues owing to the unstable nature of the fully conjugated meso-fused carbatriphyrins(2.1.1). The organo P­(V) complex of one of the meso-fused carbatriphyrins was prepared by treating the phlorin analogue of carbatriphyrin(2.1.1) with PCl3 in toluene/triethylamine at reflux for 1 h. The P­(V) complex of the meso-fused carbatriphyrin(2.1.1) was found to be moderately aromatic and the resulting global conjugation pathways in the P­(V) complex significantly alters the aromaticity of the fluorene unit. The nonaromatic nature of the phlorin analogues of the meso-fused carbatriphyrin(2.1.1) and the moderately aromatic nature of its P­(V) complex were supported by X-ray crystallography, absorption spectroscopy, NMR studies together with nucleus-independent chemical shifts, anisotropy-induced current density, and harmonic oscillation stabilization energy calculations.