4つのニッケル原子の協同作用で強固な炭素-水素結合を活性化 ―複数の金属が協力する分子の新たな可能性―

2026-07-30 京都大学

図: 4つのニッケル原子が協力して働くニッケルクラスター錯体による炭化水素C–H結合の活性化。図作成：伊豆仁助教（大木研究室）

＜関連情報＞

• https://www.kuicr.kyoto-u.ac.jp/sites/topics/260730/
• https://www.nature.com/articles/s41467-026-76006-4

芳香族および脂肪族C–H結合を可逆に活性化する四核ニッケルヒドリドクラスター A tetranuclear nickel hydride cluster capable of reversible activation of aromatic and aliphatic C–H bonds

Kohei Sunami,Tatsuya Higaki,Kanata Tanaka,Ryotaro Yamanashi,W. M. C. Sameera,Ryo Takahata,Toshiharu Teranishi,Soichi Kikkawa,Seiji Yamazoe,Takuya Shiga,Masayuki Nihei,Tatsuhisa Kato,Hitoshi Izu & Yasuhiro Ohki
Nature Communications  Published:29 July 2026
DOI:https://doi.org/10.1038/s41467-026-76006-4

Abstract

Metal cluster complexes supported by multiple hydrides are useful for activating inert bonds and molecules, while nickel-based variants capable of activating external substrates remain scarce. Here, we report a tetranuclear Ni-hydride-phosphine cluster, [Ni₄H₄(P^tBu₃)₄] (1), which we synthesize by reacting [Li(THF)_x][Ni{N(SiMe₃)₂}₃] (x ≈ 4.5 − 5) with pinacolborane (HBpin) in the presence of tri-tert-butylphosphine (P^tBu₃). Its molecular structure features a tetrahedral Ni₄ core, with four face-capping μ₃-hydrides and four terminally bound P^tBu₃ ligands. Cluster 1 is capable of reversible C–H and C–D bond cleavage of benzene-d₆, toluene-d₈, n-octane-d₁₈, and its own P^tBu₃ ligands at 50 °C, leading to H/D exchange between the deuterated solvents and the ligands in 1. This reactivity is further utilized in the catalytic hydrogen isotope exchange reaction between benzene-d₆ and toluene. The reversible dissociation of one P^tBu₃ ligand in 1 is proposed as the key step to trigger the C–H and C–D bond activation. Quantum chemical computations propose the reversible displacement of one of the P^tBu₃ ligands in 1 as the key step in triggering C–H and C–D bond activation.