Selected secondary phosphanes (HâPR2; R = Ph, Cy, iPr) smoothly react with a parent amido-bridged diiridium cyclooctadiene complex affording mixed amido/(bis)phosphido dinuclear species. A careful investigation of the reaction profile, carried out by experimental and theoretical tools, revealed that, after an initial amido/phosphido exchange, at low temperatures a second molecule of secondary phosphane adds to the dinuclear system through an oxidative addition process leading to a hydrido amido/bis(phosphido) mixed-valence complex [IrIII/IrI]. These species rearrange above â10 °C into the most stable isomer that arises from a migration of the hydrido moiety to one of the CH fragments of a coordinated cod molecule, a transformation facilitated by the formation of an intermetallic bond. Further heating of these species reductively eliminates ammonia affording bis(phosphido)-metalâmetal bonded complexes.
选定的仲膦(H→PR2;R = Ph、Cy、iPr)与母体酰胺桥二
铱环辛二烯络合物顺利反应,得到混合的酰胺/(双)
磷脂双核物质。通过实验和理论工具对反应曲线进行了仔细研究,结果表明,在初始酰胺基/
磷基交换后,在低温下,第二个仲膦分子通过氧化加成过程添加到双核系统中,形成氢基。酰胺基/双(
磷基)混合价络合物[IrIII/IrI]。这些物质在高于 10°C 时重排成最稳定的异构体,这种异构体是由氢化部分迁移到配位 cod 分子的 CH 片段之一而产生的,这是
金属间键形成促进的转变。进一步加热这些物质会还原消除
氨,从而形成双(
磷基)-
金属-
金属键合络合物。