Eilers Marcel, Bültena Saskia, Schwitalla Kevin, Schmidtmann Marc, Beckhaus Rüdiger
Institut für Chemie, Carl von Ossietzky Universität Oldenburg, D-26111 Oldenburg, Germany.
Dalton Trans. 2025 Jan 28;54(5):1972-1979. doi: 10.1039/d4dt03261f.
A series of titanium amidinato complexes were synthesized by stoichiometric insertion reactions of carbodiimides into bis(π-η:σ-η-pentafulvene)titanium complexes. NMR studies and single-crystal X-ray diffraction showed κ coordination of the former carbodiimides to the metal center. DFT calculations were performed, confirming the clear preference for a single nitrogen atom coordinating to the metal center with a high energy transition state for the formation of a chelating heteroallyl ligand. Depending on the pentafulvene ligand, additional insertion reactions of carbodiimides into the remaining Ti-C bond were observed. This allows for a stepwise insertion of the corresponding carbodiimides and offers the possibility to further functionalize the complexes. The reactivity of the remaining pentafulvene ligand is further demonstrated in reactions with H-acidic and multiple bond substrates.
通过碳二亚胺与双（π-η:σ-η-戊搭烯）钛配合物的化学计量插入反应合成了一系列钛脒基配合物。核磁共振研究和单晶X射线衍射表明，前体碳二亚胺以κ配位方式与金属中心配位。进行了密度泛函理论计算，证实了单个氮原子与金属中心配位的明显偏好，以及形成螯合杂烯丙基配体的高能量过渡态。根据戊搭烯配体的不同，观察到碳二亚胺进一步插入剩余的Ti-C键的反应。这使得相应的碳二亚胺能够逐步插入，并为进一步官能化配合物提供了可能性。剩余戊搭烯配体的反应活性在与H-酸性和多键底物的反应中得到了进一步证明。
