Two (BE)₈-[16]annulenes were prepared and fully characterized by experimental and quantum-chemical means (1, E = N; 2, E = O). The 1,8-naphthalenediyl-bridged diborane(6) 3 served as their common starting material, which was treated with [Al(NH₃)₆]Cl₃ to form 1 (91% yield) or with 1,8-naphthalenediboronic acid anhydride to form 2 (93% yield). As a result, the heteroannulenes 1 and 2 are supported by four aromatic “clamps” and may also be viewed as NH- or O-bridged cyclic tetramers of BNB- or BOB-doped phenalenyls. X-ray crystallography on mono-, di-, and tetraadducts 2·thf, 2·py₂, and 2·py₄ showed that 2 is an oligotopic Lewis acid (thf/py: tetrahydrofuran/pyridine donor). The applicability of 2 also as a Lewis basic ligand in coordination chemistry was demonstrated by the synthesis of the mononuclear Ag⁺ complex [Ag(py)₂(2·py₄)]⁺ and the dinuclear Pb²⁺ complex 6. During the assembly of 6, the rearrangement of 2 led to the formation of two (BO)₉-macrocycles linked by two BOB-phenalenyls to form a nanometer-sized cage with four negatively charged, tetracoordinated B atoms. Both 1 and 2 show several redox waves in the cathodic regions of the cyclic voltammograms. An in-depth assessment of the consequences of electron injection on the aromaticity of 1 and 2 was achieved by electronic structure calculations. 1 and 2 are proposed to exhibit aromatic switching capabilities in the [16]annulene motif.

中文翻译：

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BEB 掺杂苯酚四聚得到 (BE)8-[16] 环烯 (E = N, O)

制备了两种（BE）_8- [16]轮烯，并通过实验和量子化学手段对其进行了充分表征（1，E = N；2，E = O）。 1,8-萘二基桥联乙硼烷(6) 3作为其常见的起始原料，用[Al(NH ₃ ) ₆ ]Cl ₃处理形成1（产率91%）或用1,8-萘二硼酸处理酸酐形成2（产率93%）。因此，杂环烯1和2由四个芳香族“夹子”支撑，也可以被视为 BNB 或 BOB 掺杂苯酚的 NH 或 O 桥接环状四聚体。单、二和四加合物2 ·thf、2 ·py ₂和2 ·py ₄的 X 射线晶体学表明2是寡位路易斯酸（thf/py：四氢呋喃/吡啶供体）。通过单核Ag ⁺配合物[Ag(py) ₂ ( 2 ·py ₄ )] ⁺和双核Pb ²⁺配合物6的合成，证明了2也可作为路易斯碱性配体在配位化学中的应用。在6的组装过程中， 2的重排导致形成两个 (BO) _{9 -}大环，由两个 BOB-phenalenyl 连接，形成具有四个带负电的四配位 B 原子的纳米尺寸笼。图 1和图 2都在循环伏安图的阴极区域显示了几个氧化还原波。通过电子结构计算，深入评估了电子注入对1和2芳香性的影响。 1和2被提议在[16]轮烯基序中表现出芳香族转换能力。