Department für Chemie und Pharmazie & Interdisciplinary Center for Molecular Materials (ICMM), Friedrich-Alexander-Universität Erlangen-Nürnberg (FAU), Henkestrasse 42, 91054 Erlangen (Germany) http://www.chemie.uni-erlangen.de/tykwinski.
Angew Chem Int Ed Engl. 2014 Apr 1;53(14):3743-7. doi: 10.1002/anie.201309355. Epub 2014 Feb 26.
The use of cumulenes in synthetic transformations offers the possibility to form structurally interesting and potentially useful conjugated molecules. The cycloaddition reaction of a tetraaryl[5]cumulene with the electron-deficient olefin tetracyanoethylene affords unusual products, including functionalized dendralenes and alkylidene cyclobutanes, as well as a symmetric [4]radialene that shows unique solvatochromism, with λ(max) values approaching the near-IR region. These carbon-rich products have been investigated spectroscopically and by X-ray crystallographic analysis (five structures). The cycloaddition reaction sequence has also been explored by mechanistic and theoretical studies. The obtained results clearly demonstrate the potential of [5]cumulenes to serve as precursors for unprecedented conjugated structures.
累积二烯在合成转化中的应用为形成结构有趣且具有潜在用途的共轭分子提供了可能性。四芳基[5]累积二烯与缺电子烯烃四氰基乙烯的环加成反应生成了不寻常的产物，包括官能化的树枝状二烯和亚烷基环丁烷，以及具有独特溶剂化变色性的对称[4]轮烯，其最大吸收波长值接近近红外区域。这些富碳产物已通过光谱和 X 射线晶体学分析（五种结构）进行了研究。环加成反应序列也通过机理和理论研究进行了探索。所得结果清楚地表明了[5]累积二烯作为前所未有的共轭结构前体的潜力。
