From the Principle of Areno‐Analogy to Heterocyclopolyaromatic Compounds

Abstract

Abstract Organometallic linkage of heteroaromatic compounds provided a means of synthesizing complicated combinations of heteroaromatic compounds; not only nucleophilic aromatic substitution, but also “ArCu/ArHal linkage”, “organometallic oxidative linkage”, and “metal amide linkage” have been employed. The heterocyclopolyaromatic compounds are made of one, two, or three kinds of heteroaromatic species as ring members. These syntheses illustrate the construction of heterocycles from large, performed structural units. Competition experiments showed that the reactivity typical of the individual species is enhanced in open‐chain combinations (Ar Nu ) n and (Ar E ) n (Ar Nu , Ar E : nucleo‐ and electrophilic heteroaromatic systems, respectively); the opposite situation is mostly encountered in the case of Ar Nu A E combinations.—Cycloocta[1,2‐ b :4,3‐ b ′5,6‐ b ″:8,7‐ b ‴]tetrathiophene, the only heterocyclopolyaromatic system yet to have been studied in detail, proved surprisingly inclined to undergo monosubstitution reactions.