1,3-Diethynylbicyclo[1.1.1]pentane (DEBCP) has been found to be a valuable molecular building block mostly for the synthesis of extended, rigid, rod-like molecules. With its straightforward linear geometry, DEBCP can be used as a nonconjugated alternative to more frequently used pi-conjugated, rod-like building blocks. Examples of reactions that introduce DEBCP into larger structures are (1) the reaction of DEBCP lithium acetylides with electrophiles such as TMSCl, CO2, and Ph2PCl, (2) Sonogashira–Hagihara cross-coupling reactions with aryl or heteroaryl iodides or bromides, and (3) umpolung reactions that afford the corresponding dibromo and diiodo derivatives of DEBCP, which then successfully react with tert-C-cuprates derived from p- and m-dicarbadodecaboranes or bicyclopentanes. These umpolung reactions afforded a new class of molecular rods that combine carborane or bicyclo[1.1.1]pentane cages with ethynylene linkers. Many of the DEBCP derivatives were studied by single-crystal X-ray diffraction. They form well-organized arrays of molecular rotors, the DEBCP units, and so can be considered as examples of artificial molecular-size machines.

中文翻译：

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1,3-二乙炔基双环[1.1.1]戊烷，一种有用的分子结构单元

已发现 1,3-二乙炔基双环 [1.1.1] 戊烷 (DEBCP) 是一种有价值的分子构建块，主要用于合成延伸的刚性棒状分子。凭借其直接的线性几何形状，DEBCP 可用作更常用的 pi 共轭棒状构建块的非共轭替代品。将 DEBCP 引入更大结构的反应的例子是（1）DEBCP 乙炔锂与 TMSCl、CO2 和 Ph2PCl 等亲电试剂的反应，（2）Sonogashira-Hagihara 与芳基或杂芳基碘化物或溴化物的交叉偶联反应，以及（ 3) umpolung 反应提供相应的 DEBCP 的二溴和二碘衍生物，然后成功地与衍生自 p-和 m-dicarbadodecaboranes 或双环戊烷的叔-C-铜酸盐反应。这些 umpolung 反应提供了一类新的分子棒，将碳硼烷或双环 [1.1.1] 戊烷笼与乙炔连接体结合在一起。许多 DEBCP 衍生物通过单晶 X 射线衍射进行了研究。它们形成组织良好的分子转子阵列，DEBCP 单元，因此可以被视为人工分子大小机器的例子。