The reaction of the bidentate P,N ligand [2-(1,3,4,5-tetramethylimidazolin-2-imino)phenyl]di-tert-butylphosphine (1) with [Ir(COD)Cl]₂ (COD=1,5-cyclooctadiene) followed by addition of sodium tetrakis[3,5-bis(trifluoromethyl)phenyl]borate, NaBArF₂₄, or lithium tetrakis(nonafluoro-tert-butoxy)aluminate, Li[Al{OC(CF₃)₃}₄], afforded the complexes [(1)Ir(COD)][BArF₂₄] (2 a) and [(1)Ir(COD)][Al{OC(CF₃)₃}₄] (2 b). Exposure of 2 b to one atmosphere of dihydrogen gas afforded the diiridium tetrahydride [(1)₂Ir₂H₄][Al{OC(CF₃)₃}₄]₂ (3 b). The molecular structures of 2 a, 2 b, and 3 b were determined by single-crystal X-ray diffraction analyses. In the latter complex, the positions of the hydrogen atoms in the Ir₂H₄ core could be refined freely, which had previously proved impossible for the corresponding complex 3 a containing the BArF₂₄ anion. Since 2 a is an established catalyst for ortho-directed hydrogen isotope exchange (HIE), the performance of 2 a and 2 b in deuterium labelling reactions was compared for various substrates, including phenylacetic acid derivates and nitrogen-containing aromatic compounds.

中文翻译：

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Phosphine-Imidazolin-2-Imine Iridium(I) 氢同位素交换催化剂的最新进展

双齿P , N配体[2-(1,3,4,5-四甲基咪唑啉-2-亚氨基)苯基]二叔丁基膦( 1 )与[Ir(COD)Cl] ₂ (COD=1 ,5-环辛二烯)，然后添加四[3,5-双(三氟甲基)苯基]硼酸钠、NaBArF ₂₄或四(九氟-叔丁氧基)铝酸锂、Li[Al{OC(CF ₃ ) ₃ } ₄ ], 得到配合物 [( 1 )Ir(COD)][BArF ₂₄ ] ( 2 a ) 和 [( 1 )Ir(COD)][Al{OC(CF ₃ ) ₃ } ₄ ] (2b）。将2 b暴露于一个氢气气氛，得到四氢化二铱 [( 1 ) ₂ Ir ₂ H ₄ ][Al{OC(CF ₃ ) ₃ } ₄ ] ₂ ( 3 b )。2a、2b和3b的分子结构通过单晶X射线衍射分析确定。在后一种络合物中，氢原子在 Ir ₂ H ₄核中的位置可以自由调整，这在之前已被证明对于相应的络合物3 a是不可能的含有 BArF ₂₄阴离子。由于2a是一种既定的邻位氢同位素交换 (HIE)催化剂，因此比较了2a和2b在各种底物（包括苯乙酸衍生物和含氮芳香族化合物）的氘标记反应中的性能。