Stable pseudotetrahedral supermolecules based on an oxoporphyrinogen

Topologically asymmetric compounds, important as chiral nanoscale building blocks, were synthesized using stepwise N-alkylation on tetrakis(3,5-di-t-butyl-4-oxocyclohexadien-2,5-yl) porphyrinogen as revealed by X-ray crystallographic studies on a porphyrinogen molecule bearing four different N-substituents.