This review focuses on the heavier group 13–15 element-containing heterocycles of [4n+2]-electron systems featuring classical and advanced aromatics.

It has been computationally proposed that there are more than 200 possible isomeric structures for the C6H6 molecule, among which benzene (CH)6 represents the most thermodynamically stable molecule and its chemistry has been extensively developed. Three benzene valence isomers (CR)6, namely, prismane, Dewar benzene, and benzvalene, have also been synthesized to date. Incorporation of heteroatoms in the skeletal frameworks allows access to inorganic analogues of benzene and its valence isomers, which have attracted considerable attention due to their peculiar structural and electronic features. Experimentally, more than 30 examples of inorganic benzene and its valence isomers have been developed and characterized so far. In this contribution, their synthesis and characterization, as well as their stability and chemical properties, are discussed.

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Strained hydrocarbons constitute one of the most prominent classes of organic compounds. Among them, bicyclo[2.1.0]pentene ("housene") derivatives represent a highly challenging and very attractive class. Although organic housenes have been known for more than five decades, there are still very few of them containing heavier main group elements. In this paper, we report on the two housene-type structures, novel monomeric stibahousene and dimeric bis(stibahousene). The bonding natures of both compounds were approached from both experimental and computational directions to reveal their peculiar structural features.

A neutral 1,4‐diaza‐2,3,5,6‐tetraborinine derivative (3) featuring a 6π ring system has been synthesized and structurally characterized. The prospective aromatic nature of 3 was assessed by single‐crystal X‐ray analysis, NMR, and UV/Vis absorption spectroscopy as well as computational studies. Furthermore, preliminary reactivity investigations showed that 3 does not only react with diphenyl acetylene but also readily captures CO2 in a [4+2] cycloaddition under ambient conditions.