Maiola Michela L, Buss Joshua A
Willard Henry Dow Laboratory, Department of Chemistry, University of Michigan, 930 N. University Avenue, Ann Arbor, MI 48109, USA.
Angew Chem Int Ed Engl. 2023 Nov 27;62(48):e202311721. doi: 10.1002/anie.202311721. Epub 2023 Oct 27.
We employ a metal-metal salt metathesis strategy to access low-valent tantalum-copper heterometallic architectures (Ta-μ -H -Cu and Ta-μ -H -Cu ) that emulate structural elements proposed for surface alloyed nanomaterials. Whereas cluster assembly with carbonylmetalates is well precedented, the use of the corresponding polyarene transition metal anions is underexplored, despite recognition of these highly reactive fragments as storable sources of atomic M . Our application of this strategy provides structurally unique early-late bimetallic species. These complexes incorporate bridging hydride ligands during their syntheses, the origin of which is elucidated via detailed isotopic labelling studies. Modification of ancillary ligand sterics and electronics alters the mechanism of bimetallic assembly; a trinuclear complex resulting from dinuclear C-H activation is demonstrated as an intermediate en route to formation of the bimetallic. Further validating the promise of this rational, bottom-up approach, a unique tetranuclear species was synthesized, featuring a Ta centre bearing three Ta-Cu interactions.
我们采用金属-金属盐复分解策略来制备低价钽-铜异金属结构（Ta-μ-H-Cu和Ta-μ-H-Cu），这些结构模拟了表面合金化纳米材料中提出的结构单元。虽然用羰基金属酸盐进行簇组装已有充分的先例，但相应的多芳烃过渡金属阴离子的使用却未得到充分探索，尽管这些高反应性片段被认为是可储存的原子M源。我们对该策略的应用提供了结构独特的早期-晚期双金属物种。这些配合物在合成过程中包含桥连氢化物配体，通过详细的同位素标记研究阐明了其来源。辅助配体空间位阻和电子效应的改变会改变双金属组装的机制；双核C-H活化产生的三核配合物被证明是双金属形成过程中的中间体。进一步验证了这种合理的自下而上方法的前景，合成了一种独特的四核物种，其特征是一个Ta中心具有三个Ta-Cu相互作用。
