In comparison to the omnipresent two- and three-dimensional allotropes of carbon, namely, graphite and diamond (as well as recent entries graphene, carbon nanotubes, and fullerenes), a detailed understanding of the one-dimensional carbon allotrope carbyne is not well established, and even the existence of carbyne has been a matter of controversy over the past decades. Composed of sp-hybridized carbon, carbyne could potentially exist in two forms, either as a polyyne (alternating single and triple bonds, expected to show a semiconducting behavior) or as a cumulene (all carbon atoms are connected via double bonds, predicted to show metallic behavior). Although a number of publications are available on the hypothetical structure and properties of carbyne, specific knowledge about its physical and spectroscopic characteristics is still unclear. In order to predict the properties of carbyne, the synthesis and study of model compounds, namely, polyynes and cumulenes, has been a promising avenue. The synthesis of polyynes has been extensively explored in the last decades, culminating with the isolation of a polyyne with 22 acetylene units, which allows extrapolation to the properties of carbyne. Extended cumulenes, on the other hand, have remained much less well-known, and specific studies of properties versus molecular length are quite limited. A limiting factor to the study of [n]cumulenes has been their dramatically increased reactivity, especially in comparison to polyynes of comparable length. For example, most known [7]cumulenes can only be handled in solution, while the polyynes of equivalent length (i.e., a triyne with three acetylene units) are quite stable. [9]Cumulenes are the longest derivatives studied to date.

中文翻译：

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奇数[ n ]异丙苯（n = 3、5、7、9 ）：合成，表征和反应性

与无所不在的二维和三维碳同素异形体，即石墨和金刚石（以及最近进入的石墨烯，碳纳米管和富勒烯）相比，对一维碳同素异形体卡宾炔的详细理解尚不清楚，甚至在过去几十年间，一直存在争议的是碳炔。碳炔由sp杂化碳组成，可能以两种形式存在，即多炔（交替的单键和三键，预期表现出半导体性能）或异丙苯（所有碳原子通过双键连接，预期显示）金属行为）。尽管有许多关于碳炔的假设结构和性质的出版物，但是关于其物理和光谱特征的具体知识仍然不清楚。为了预测碳炔的性质，合成和研究模型化合物即聚炔和聚对苯二酚一直是一个有前途的途径。在过去的几十年中，对聚炔的合成进行了广泛的探索，最终以分离出具有22个乙炔单元的聚炔为最终手段，从而可以推断出炔的性质。另一方面，扩展的对苯二酚还不太为人所知，并且关于分子长度与性质的关系的具体研究非常有限。研究[ 可以外推到卡宾分子的性质。另一方面，扩展的对苯二酚还不太为人所知，并且关于分子长度与性质的关系的具体研究非常有限。研究[ 可以外推到卡宾分子的性质。另一方面，扩展的对苯二酚还不太为人所知，并且关于分子长度与性质的关系的具体研究非常有限。研究[n ] cumulenes的反应活性得到了极大提高，特别是与可比长度的聚炔相比。例如，大多数已知的[7]枯草酮只能在溶液中处理，而等长的聚炔（即具有三个乙炔单元的三炔）非常稳定。[9] Cumulenes是迄今为止研究最长的衍生物。