Dinaphthoporphycenes

Abstract

Naphthobipyrrole is a potentially useful building block for porphyrin and porphyrin analogue synthesis. Reported here is a simple, generalizable synthetic route to α-formylated, β-substituted naphthobipyrroles and their use in the preparation of binaphthoporphycenes. The resulting binaphthoporphycenes possess a planar geometry as determined via a single-crystal X-ray diffraction analysis; they also display absorption maxima that are bathochromically shifted compared to simple porphycenes.

Figure 1

¹H NMR spectra (low field portion) of porphycene 3a in toluene-d₈ at 27 °C (bottom) and 100 °C (top).

Figure 2

UV-vis spectra for 3a and 3b recorded in dichloromethane (0.11 mM).

Figure 3

Three orthogonal views of the X-ray structure of 3b. All hydrogen atoms bound to carbon atoms are omitted for clarity. Thermal elipsoids were scaled to the 50% probability level.

Scheme 1

General route to disubstituted naphthobipyrroles.