Touchton Alexander J, Wu Guang, Hayton Trevor W
Department of Chemistry and Biochemistry, University of California Santa Barbara California 93106 USA
Chem Sci. 2022 Apr 11;13(18):5171-5175. doi: 10.1039/d2sc00960a. eCollection 2022 May 11.
Reaction of [Ni(1,5-cod)] (30 equiv.) with PEt (46 equiv.) and S (1.9 equiv.) in toluene, followed by heating at 115 °C for 16 h, results in the formation of the atomically precise nanocluster (APNC), [NiS(PEt)] (1), in 14% isolated yield. Complex 1 represents the largest open-shell Ni APNC yet isolated. In the solid state, 1 features a compact "metal-like" core indicative of a high degree of Ni-Ni bonding. Additionally, SQUID magnetometry suggests that 1 possesses a manifold of closely-spaced electronic states near the HOMO-LUMO gap. monitoring by ESI-MS and P{H} NMR spectroscopy reveal that 1 forms the intermediacy of smaller APNCs, including [NiS(PEt)] and [NiS(PEt)] (2). The latter APNC was also characterized by X-ray crystallography and features a nearly identical core structure to that found in 1. This work demonstrates that large APNCs with a high degree of metal-metal bonding are isolable for nickel, and not just the noble metals.
在甲苯中，将[Ni(1,5-环辛二烯)]（30当量）与三乙膦（46当量）和硫（1.9当量）反应，然后在115℃加热16小时，以14%的分离产率得到原子精确的纳米团簇（APNC）[NiS(PEt)]（1）。配合物1是迄今分离出的最大的开壳层镍APNC。在固态下，1具有紧凑的“类金属”核心，表明存在高度的镍-镍键合。此外，超导量子干涉仪磁力测定表明1在HOMO-LUMO能隙附近拥有一系列紧密间隔的电子态。通过电喷雾电离质谱（ESI-MS）和磷-31核磁共振波谱（P{H} NMR）监测发现，1形成了较小APNC的中间体，包括[NiS(PEt)]和[NiS(PEt)]（2）。后一种APNC也通过X射线晶体学进行了表征，其核心结构与在1中发现的几乎相同。这项工作表明，具有高度金属-金属键合的大型APNC不仅对于贵金属是可分离的，对于镍也是如此。
