Organometallic moieties attached to substrates via π-complexation play an important role as auxiliaries. As described in the present review, η-linked auxiliaries have been employed to overcome numerous synthesis obstacles that continue to present significant challenges for catalyzed reactions. This has been particularly true in carbon-carbon bond forming reactions involving highly unsaturated systems such as arenes, dienes and allenes, which are emphasized here.

中文翻译：

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π 络合有机金属助剂促进碳-碳键形成：概述

通过 π 络合与底物连接的有机金属部分作为助剂发挥着重要作用。如本综述所述，η-连接的助剂已被用于克服许多合成障碍，这些障碍继续对催化反应提出重大挑战。这在涉及高度不饱和系统如芳烃、二烯和丙二烯的碳-碳键形成反应中尤其如此，这里强调这些。