Well-defined, bimetallic molecular clefts: A new approach to nitrogen fixation and transformation

一种新的大环支架已经被开发出来，它将有助于构建创新的双金属分子，其中金属的直接环境和并置都由设计来定义。这些化合物采用的铰链或Pacman拓扑结构将通过提供定义明确且易于研究的反应口袋，帮助促进科学上独特的、潜在的商业利用的氮化学。首先，将考虑用于氮转化的新的、低价的、早期过渡金属(钛、锆、钒、镧)Pacman化合物的制备和表征。这是一种原创的、预制的双核方法来激活氮素，并将产生非碎片化合物，这些化合物准备与有机底物反应，形成新的N-E键(E=H，C，Si)。这些新化合物的反应活性将通过对金属的明智选择和对配体外围的合理修饰来控制。氢化、硅基化、环加成和N原子转移反应将被评价为将二氮源衍生的N结合到有机底物中的化学计量和催化途径。

A new macrocyclic scaffold has been developed that will assist in the construction of innovative bimetallic molecules where both the immediate environment and juxtaposition of the metals are defined by design. The hinged, or Pacman topology that these compounds adopt will help promote scientifically unique and potentially commercially exploitable chemistry of nitrogen by providing a well-defined and easily-studied reaction pocket. Initially, the preparation and characterisation of new, low valent, early transition metal (titanium, zirconium, vanadium, lanthanides) Pacman compounds for dinitrogen transformation will be considered. This is an original, prefabricated dinuclear approach to dinitrogen activation and will yield nonfragmentary compounds that are primed to react with organic substrates to form new N-E bonds (E = H, C, Si). The reactivity of these novel compounds will be controlled by judicious choice of metal and reasoned modification of the ligand periphery. Hydrogenation, silylation, cycloaddition and N-atom transfer reactions will be evaluated as stoichiometric and catalytic routes to the incorporation of dinitrogen-derived N into organic substrates.