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Abstract Octalenobisterphenylene1(also known as terphenylene dimer) was synthesized from 3,3′,5,5′‐tetraaryl‐substituted biaryl bytert‐butyllithium‐mediated cyclization followed by oxidative coupling. This one‐pot two‐step protocol facilitated the successive formation of four four‐membered and two eight‐membered rings. Treatment of1with sodium metal, followed by crystallization from THF, yielded the remarkable diradical dianion [(1^•–)₂]²⁻, where the two molecular halves are connected by four σ bonds. The cyclodimerization is driven by the pronounced reactivity and strain of the central six‐membered ring within the [3]phenylene subunit. The structure and diradical nature of [(Na⁺)₂(1^•–)₂] were confirmed through X‐ray crystallography, DFT computations, and¹H NMR and ESR spectra. These investigations revealed that the two spins, one on each molecular half, exhibit minimal mutual interaction. 

Abstract The chemical reduction of a bilayer spironanographene,spiro‐NG(C₁₃₇H₁₂₀), with Na and K metals in the presence of [2.2.2]cryptand to yield [Na⁺(2.2.2‐cryptand)](C₁₃₇H₁₂₁⁻) (1) and [K⁺(2.2.2‐cryptand)](C₁₃₇H₁₂₁⁻) (2), respectively, is reported. X‐ray crystallography reveals the formation of a new “naked” anion (spiro‐NG_H⁻), in which spirocyclic ring cleavage and subsequent hydrogenation have occurred. Density Functional Theory (DFT) calculations suggest that the generation of the radical anion of the parent nanographene (spiro‐NG^•−), upon electron acceptance from Na and K metals, induces the cleavage of the strained spirobifluorene core. The resulting spin density localizes on a particular carbon atom, previously attached to the spiranic sp³carbon atom, facilitating a site‐specific hydrogenation to afford (spiro‐NG_H⁻). The electrostatic potential map of this anion reveals electron density concentrated at the five‐membered ring of the readily formed indenyl fragment, thus enhancing the aromaticity of the system. Furthermore, nuclear magnetic resonance (NMR) and UV–vis absorption spectroscopy experiments allowed to follow the in situ reduction and hydrogenation processes in detail.