Szych Lilian S, Denker Lars, Feld Joey, Goicoechea Jose M
Department of Chemistry, University of Oxford, Chemistry Research Laboratory, 12 Mansfield Road, OX1 3TA, Oxford, U.K.
Department of Chemistry, Indiana University, 800 E. Kirkwood Ave, 47405-7102, Bloomington, IN, U.S.A.
Chemistry. 2024 Jun 17;30(34):e202401326. doi: 10.1002/chem.202401326. Epub 2024 May 14.
We describe our efforts to access a compound with an Al=P double bond by reaction of Al(Nacnac) towards [HCN(Dipp)]P(PCO) (Nacnac=HC[C(Me)N(Dipp)]; Dipp=2,6-PrCH). Our observations are consistent with the formation of a transient phosphanyl-phosphaalumene at low temperatures (-70 °C), however this species was found to readily undergo intramolecular C-H activation of the β-diketiminato ligand upon warming to room temperature. The reactivity of the transient complex toward small molecules including dihydrogen, carbon dioxide, phosphaketenes, amines and silanes could be explored at low temperatures, showcasing that the target compound can react as both a frustrated Lewis pair (via the pendant phosphanyl moiety) or in hydroelementation reactions of the Al=P bond. The elusive target molecule could be trapped by addition of a Lewis base (tetrahydrofuran) affording an isolable molecular species that reacts in an analogous fashion to the base-free compound.
我们描述了通过将Al(Nacnac)与[HCN(Dipp)]P(PCO)反应来获取具有Al=P双键的化合物的过程（Nacnac = HC[C(Me)N(Dipp)]；Dipp = 2,6-PrCH）。我们的观察结果与在低温（-70°C）下形成瞬态膦基-磷铝烯一致，然而发现该物种在升温至室温时容易发生β-二酮亚胺配体的分子内C-H活化。可以在低温下探索瞬态配合物对包括氢气、二氧化碳、磷烯酮、胺和硅烷在内的小分子的反应性，这表明目标化合物既可以作为受阻路易斯对（通过侧链膦基部分）反应，也可以在Al=P键的加氢元素化反应中反应。通过加入路易斯碱（四氢呋喃）可以捕获难以捉摸的目标分子，得到一种可分离的分子物种，其反应方式与无碱化合物类似。
