Molecules containing multiple bonds between atoms-most often in the form of olefins-are ubiquitous in nature, commerce, and science, and as such have a huge impact on everyday life. Given their prominence, over the last few decades, frequent attempts have been made to perturb the structure and reactivity of multiply-bound species through bending and twisting. However, only modest success has been achieved in the quest to completely twist double bonds in order to homolytically cleave the associated π bond. Here, we present the isolation of double-bond-containing species based on boron, as well as their fully twisted diradical congeners, by the incorporation of attached groups with different electronic properties. The compounds comprise a structurally authenticated set of diamagnetic multiply-bound and diradical singly-bound congeners of the same class of compound.

中文翻译：

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乙硼烷及其90°扭转双自由基同系物的分离。

在自然界，商业界和科学界普遍存在的原子之间具有多个键的分子（最常以烯烃的形式存在），因此对日常生活产生了巨大影响。考虑到它们的突出性，在过去的几十年中，人们进行了许多尝试来通过弯曲和扭曲来扰动多结合物种的结构和反应性。然而，在完全扭曲双键以均质地裂解相关的π键的探索中，仅获得了适度的成功。在这里，我们介绍了通过结合具有不同电子性质的连接基团来分离基于硼的含双键物质及其完全扭曲的双基同系物。